to try and put what may be referred to as the issue with youview as it is into different words is:
freeview in itself is great for watching telly that is planned in advance, you look at the epg and schedule a recording for what you want. That recording is then available for as long as you like to watch as many times as you like.
The youview element, or let's just say the internet catch-up facility of it, is a retrospective viewing of something you missed - but in the case of bbc (at least), there is only programmes available for the last 7 days... so you are time limited in when you can catch up, and it limits the possibility of watching again and again. So that's the current 'bind' that some would say detract from the potential of youview.
I can't say I 've done it for a while, but on the computer, I was able to download iplayer content and then watch later (much later if i stripped the DRM

), so some would argue why youview could not have included that in their spec. Why is stuff that you didn't record yesterday restricted, but the stuff you schedule to record today unrestricted (copy it to PC, put on dvd, whatever)?
Anyhoo, I'm in a quandary of whether to save up to buy youview, or just spend less on plain 'ole freeview. Our 9200 is getting a bit long in the tooth now. If I can get my raspberry pi doing the internet catch-up thing well, then it's a no-brainer for me. Unless comet offer some kind of discount (as I can get 10% of them through work anyway, so any additional discount would make youview more attractive).
I would guess (and this along the lines of Clem's comment) that at some point Youview (the catch-up element thereof) will be avilable as a software plugin of some sort to enable it to run on computers, consoles et al, but first they have to sell some hardware to recoup the development costs.