Thedoccal
Midi won't work for online collaboration.  Audio only.
But midi works for creating what will end up being that collaborative audio file.
So midi will stay...at least in the Sonar version that Bandlab adopts for it's platform.

Depending on what you mean by online collaboration, this is not necessarily true. I have collaborated many times using MIDI.  If the person you are working with has the same MIDI instruments, not a problem at all to send them the file, then they can work on it, and send it back.  

If they do not have the same instruments, still not a problem...you just say "Track 1 = Piano, Track 2 = Bass", etc.  They can then setup something close or similar on their end, create their track and send it back.  I've done it plenty of times. 

The General Midi standard was a handy invention.  It pays to have a Roland Sound Canvas lying around to play back midi files correctly.  It does work and rather well.  Selecting instruments, setting up mixes and effects.  I have collaborated this way sending GM ideas back and forth and then at the right time replacing the GM sounds with better quality sounds.  It is a good format for commercial midi files of covers.  Many midi files setup and playback perfectly. 
 
GM sounds can be edited too and dropped into the music anywhere. 
 
 

Jeff Evans
Sonar was as far as I remember not considered the midi king back at the time.  It was Cubase and Logic.  Both of those programs handle midi real well in fact.  They were both in existence for 6 to 7 years before Cakewalk started.  I started with Steinberg Pro 24 for the Atari too.  That was pretty cool at the time.  Sonar has also had a long association with midi though for sure. 

Cubase appears to have it's start in 1984 on the Commodore 64 with Pro-16 by Steinberg. The Atari ST was released in 1985 so that is the earliest for C-Lab Creator (which eventually became Logic). Cakewalk version 1.0 was in 1987 on MS-DOS machines. So at best Cubase has a three year longer history, Logic, has two years, over Cakewalk. Cakewalk and then SONAR have always had MIDI. There were other Cakewalk branded products that might have skimped on MIDI, but SONAR doesn't skimp.
 

Jeff Evans
The General Midi standard was a handy invention.  It pays to have a Roland Sound Canvas lying around to play back midi files correctly.  It does work and rather well.  Selecting instruments, setting up mixes and effects.  I have collaborated this way sending GM ideas back and forth and then at the right time replacing the GM sounds with better quality sounds.  It is a good format for commercial midi files of covers.  Many midi files setup and playback perfectly. 
 
GM sounds can be edited too and dropped into the music anywhere. 
 

I have an old Roland JV1080 rack module that can play back GM sounds. 
 
But as far as GM compatibility built into DAWs, Sonar has TTS-1, and Studio One has Presence XT.  I believe Cubase can also open GM in the included Halion Sonic, but I have not tried that.
 
I think that TTS-1 has a slight edge on Presence XT, but both definitely need some sounds replaced with better instruments.  Either way, it is handy to be able to open a file with sounds loaded, and have an idea what the orchestration should ultimately be.  The instrument names in the GM file alone are a big help in finding substitute sounds that correspond with the original composition.  If you have a multi-timbral sampler it is easy to substitute channel by channel for the GM sounds as needed.

abacab
 Selecting instruments, setting up mixes and effects.  I have collaborated this way sending GM ideas back and forth and then at the right time replacing the GM sounds with better quality sounds.  It is a good format for commercial midi files of covers.  Many midi files setup and playback perfectly. 
 
GM sounds can be edited too and dropped into the music anywhere. 
 

I believe Cubase can also open GM in the included Halion Sonic, but I have not tried that.


Yes, that is correct.

abacab
I believe Cubase can also open GM in the included Halion Sonic, but I have not tried that.

Yes, that is correct.

Stay

Dropping midi is like asking people to stop breathing because 'second hand smoke'.
 
I admit, in my younger days when I used to smoke, I had a sticker on my dashboard that read "Thank you for holding your breath while I smoke!"...

  I have an original Korg MS-20, Poly 6, Poly 61, and M1, and a Yamaha DX7 all dead now.
I also have an old Roland Super JV-1080, ROMed out to the max with all expansion card slots filled. An old Juno (retired), and a PMA-5 portable 8 track sequencer Sound Canvas module that I've rocked many a solo performance with over the years. The Roland PMA-5 can store 20 songs and can run off batteries for about 12 hours of continuous use. All my old Roland's still work great. The old Juno still work but is retired because C4 key lost touch sensitivity.
 I also have an old Kawai K 11 (circa 1990) in excellent shape which is my absolute favorite very high quality sounding 32 bit GM digital hardware synth in the studio to date. It actually has two 16 bit sounds engines and 2 MIDI ports. It's still one of my go to choices for realistic piano and horns.
 But what makes the K 11 really shine is the feel and action. It's everybody's who has ever touched it favorite choice to use as keyboard controller for playing ANY synth.
 It has an extremely wide and smooth velocity range giving it a very natural feel from soft to loud, which makes it also an excellent choice for banging out and sequencing sampled drum tracks with Addictive Drums 2.
 I've been creating drum tracks on MIDI keyboards for decades. Thank God the bakers at XLN Audio has the grace and insight to included the standard GM MIDI map for drums, or I probably wouldn't have realized how good AD 2 and their sampling techniques are.
 Bye bye ToonTracks it was great and much fun while it lasted.. ;-p
 And THANKYOU Cakewalk for including Addictive Drums with SONAR Platinum
 
 I really like the Cakewalk TTS-1 DXi synth, especially being that it has such a wide list selection of varieties of Roland Sound Canvas GM/GS version libraries. Very customizable and specific to dozens of Roland synth voicings put out through the years. I've been using the TTS-1 as the center piece for all my GM collaborations since it was introduced with SONAR 4 PE, and still use it today.
 I also love the fact that it can be configured to 4 separate audio output channels giving it that much more flexibility and precise control over the sound of each voice or instruments using EQ and or any other audio FX you choose.
 I never patch more then one voice per output for optimal sound quality, no need to when I can just open another instance of the TTS-1.
 And just because you can play perform 16 different parts on a GM synth doesn't mean you should, because the more voices and parts being pumped through any synth's sound engine, be it software or hardware the more the over all sound quality degrades.
 Of course distortion has it's place in many situations, but SONAR has a host of audio FX that will nasty things up in a very musical way.
 
 The GM spec is most likely the most important key to successful MIDI collaboration that ever happened.
 Developed in collaboration with Roland, Cakewalk, Microsoft, and defined by IEEE for a standard set of 128 algorithms for program and control changes.
 It's the closest way to get all synth manufacturers on the same page by defining a specific set RPNs (registered parameter numbers), and leaving enough room with NRPNs (non registered parameter numbers) for manufacturer proprietary system exclusive information that simply gets ignored by synths that don't support or understand it.
 
And I gotta give BIG PROPS to Rapture Pro, what with being Dimension Pro and Rapture bundled up together in one Killa arse powerful GUI interface is well........... Not GM, but its ANY type of synth you want it to be. I have all the Dimension Pro expansion packs, plus several I purchased from Digital Sound Factory.
 If I was ever forced to chose between using any one synth, Rapture Pro would be the no brainer choice for the all in one Superstar.
 Now I know there are many here who would say something like; "Oh dude, you really need to try N.I.'s Kontakt!" and I know it's good just by the things I've heard from it.
 But I don't need to try it because I don't need it and I'm already familiar with what I have..

Wow, Steev... thanks fer the dynamite essay that highlighted the crucial importance of MIDI... rawk on!