I'm staying right here.

All this talk of what now, what next is making me crazy. I'm using Sonar until it grinds to a halt. With a little luck we can find a work around for the installation issue and carry on. I don't want to learn anything else and I don't want to get back on the DAW merry-go-round. I see a number of folks are prepping alternate forum sites. That's very commendable but I don't want to see the community spread all over the web. Those that are setting these things up should communicate a bit so we don't end up with a handful of Cakewalk Sonar web sites.
I'm, going to stay right here until the lights go out. After that I'll be using the site Panu has set up. He was way ahead of all this and has given selflessly to the community for years. I feel I owe him.

I agree - nothing is gonna change for a while, and even if the authentication servers go, SONAR will work until you change your PC.
 
I'm sure when the dust settles, we can all have a calm discussion about what to do next ;-)

Me Too. 
I'm going install and update Sonar on all of my computers so I'll have backups.
I would never go as far back as 8.5 but X3e was solid as a rock and that will always be usable becuase it does not require any on line activation. It uses the good old serial and activation codes.  So say 5 years from now when Splat dies I have the option to return to X3. 
I also have a full licence and activation for Professional so that's 2 computers. 
I have Home Studio, that's 2 more and I will say that other than missing Drum replacer and Melodyn,, I like Home studio and if it's all I had I'd be still doing what I'm doing. 
And Splat which I have on 3 computers right now but only can fully use 2 because of AD2 and Air activations only allow 2. 
An interesting thing I found out was Melodyn works for drag and drop audio to a midi track convertion without activation. I was suprised when I installed Splat to a new computer , the 3rd, and without thinking I draged a audio bass track to a midi track and melodyn did it's thing. 

Well Craig, I don't think Sonar is considered the premier midi platform, isn't that Cubase? I just can't handle another learning curve. I have other options with Studio 1 and Harrison Mixbuss, but I don't want them. I want my Sonar. 

The biggest problem I see with sticking with what we have isn't that it will stop working, but (for example) it won't incorporate some beneficial changes to the MIDI spec scheduled out over the next year or two.

 
For me the biggest headache is if I can't go in and tweak something (in a mix, for example) 2 years from now.
 
If we get a version that stops needing authentication (esp if we change PC) that would be really good.
Otherwise, I guess we just go find a cracked version ;-)

Anderton
I don't think it's a digital situation where one day you're using SONAR, and one day you're not.

Did you mean 'binary'
 
There are 10  types of people in the world. Those who understand binary and those that don't

I’ll stick with Sonar but develop my Raven, PT, Waves and Digigrid setup