"And as for Vegas Pro, what is left for them to do with it?"
Oh not much. Just port it over to full assembly so it runs from a 10MB executable about 10 times faster than it does now. And while they're at it fix all of the bugs.
Yes, the outdated under-the-hood APIs/Libraries are quite outdated.
Updating to the latest CUDA and openCL would be nice.
Someone recently posted that VP is based on VFW only - not D.X
Obviously, major structural changes would require substantial
rewrites - perhaps that's why they've taken so long to produce
an update.
There is not going to be any VegasPro re-write of any base code.
Turn your attention to Catalyst Prepare and Edit suite, if you want to follow SCS into the future.
The VP12 to VP13 paid upgrade -- hands up who really got some actual benefit from it, i.e. in some way that you didn't already do in some other software, e.g EBU R128). SCS have a moral obligation to either declare VP dead, OR state categorically that the future development path is towards Catalyst (kind of obvious really) AND that faithful VP fan will be taken care of (hopefully not in a Hoffa kind of way ....)