That's all great really but I wouldn't call those DSP's advanced if they can't process 720p h.264 high profile video with average 5 mbits
Wow, poor DSP designers, I think you just insulted every single one of them that has ever lived...
I'm certainly not aware of 720p H.264 High Profile having shipped in a commercial product using a classic DSP and no accelerator even for the tight loops... But then again I guess you meant a DSP+Accelerator approach probably.
I know I'm being picky but IMO only baseline profile is useless. Especially on something that want's to be a small computer (MID, netbook, nettop etc.) and HD PMP.
I can hear people at NVIDIA crying right now! j/k (and quite a few other companies too, I'm not sure anyone but TI & Apple is doing High Profile in their next-gen SoCs). Anyway to address your reason:
It would mean that every 720p BDrip would have to be re-encoded.
Wow, a 720p library not being usable until the ends of time... shock horror
How many people already have their library of BDrips anyway? Seems like a niche of a niche to me. And this generation nobody supports High Profile, by next generation everyone will be 1080p so you'd have to re-encode anyway. Plus 5mbps is not very high so you'd probably want to encode it again on a SoC that supports 10-20Mbps. Finally, consider that even OMAP4 doesn't support bitrates anywhere near high enough to play any Bluray stream without transcoding.
BTW, when it comes to image quality, it's worth pointing out that many more SoCs will support VC-1 Advanced Profile than H.264 High Profile/CABAC, and the former's image quality is obviously better than H.264 Baseline. So if you can find a good VC-1 encoder, that's probably the way to go.
Even youtube HD would be too much
Yeah, that's definitely very unfortunate, and is probably the best use-case I can think of where the user would be pissed off because he wouldn't understand why it doesn't work on an ARM netbook that is claimed to be so awesome at HD playback.
Another point, I think, is that practically all HD content that won't require any illegal process to obtain (zomg, bypassing HDCP! the horror!) won't be High Profile - in part because the devices don't support it, of course. But Youtube is certainly a big exception there, and does make it look pretty dumb, heh...
Don't get me wrong, I'd love every SoC in the world to have a PowerVR VXD 380 running at 300MHz so it could handle two simultaneous streams of 1080p H.264 High Profile at 40Mbps+... But I don't think that's realistic at this point
It would be extremely amusing if Apple was the first to come out with that - I wouldn't be overly optimistic at this point though. Ah well, we'll see what happens.