I recently had the opportunity to run a couple of recording sessions using Pro Tools HD. As I understand it, the power in PT HD actually lies in the hardware that includes it's own processors. I have to say that the sound was really big and fluid. My question as a loyal CW user (started on Cakewalk 4), will CW ever do something comparable with it's platform/hardware? Maybe this is a stupid question or observation. Any thoughts?? 

I would say it's not likely...

And, actually, the capability is already there in a way...

Waves Digigrid system offers hardware integration with
any DAW and Waves plugins.  Not in the same way
as PT HD...but it is THERE.
 
Also, UAD offers hardware integration with UAD Plugins
and any DAW...and UAD Plugins are considered some
of the best out there...

Also, Pro Tools Standard now has most of the capabilities 
of HD, without the hardware...so that line is also being blurred
if you will...

I'm going to just say that it's my impression that Pro Tools came of age in a time when CPU power was limited, so using outboard hardware with DSP's took the processing load off of the CPU, which was a reasonable approach.
 
Not sure that would be my first choice today.

abacab
I'm going to just say that it's my impression that Pro Tools came of age in a time when CPU power was limited, so using outboard hardware with DSP's took the processing load off of the CPU, which was a reasonable approach.
 
Not sure that would be my first choice today.

This.
 
Try getting a top of the line interface (OP your Roland quad capture isn't one) to put in front of Sonar and make sure you have a powerful computer and the ProTools HD model won't look so glamorous.  

Cake and roland tried to make a hardware system(s), the VS 700.  Great hardware but the built-in effects were barely passable and not in line w/ PT - or SONAR.
 
And PT is the standard now for pro studios because of the hardware acceleration they used back when.  You needed  hardware acceleration just to record stereo tracks in the early 90s and PT continued with hardware to alieve latency, provided intensive DSP modeling and as a kind of dongle (tho that is no longer necessary).  I was just at a friend's studio and he was stripping out old cards, putting them on ebay and replacing them with new DSP cards.  I didn't ask him how much the new ones were since he was complaining about how much the old ones cost and he couldn't get anything for them now.
 
Cake is good at using native DSP, and it is far cheaper to buy a better computer than for Cakewalk to "add" DSP to run along side native.  No doubt TASCAM could come up with something, but it is a financial crap shoot.  The UA accelerator/dongle used to be the hottest thing - not so much anymore since there are good native equivalents that aren't inherently bottlenecked for DSP.  You need to be open (not only to other daws but to apple too) or you end up with the Roland unit - excellent hardware that is locked into SONAR.  Unfortunately not enough of us could (can) justify $2000 for a controller.  Avid can afford to do hardware since so many pro studios are "locked in" and can afford to pay the price to keep up with the Jones.  The Avid console units are excellent and are cheaper than most any analog desk they replace and there are enough users/buyers to break even or make a profit.
 
Between computers that can run the entire world, better drivers for interface latency and touchscreen control I doubt that Gibson will pay for DSP cards or an expensive DAW controller that doesn't seem to have a future.