Given the rest of the features they discussed last night, if lack of native backwards compatibility is the one thing that will make you not buy the system, you have weird priorities.
I see a lot of people harp on the compatibility issue, to be honest, and yet the vast majority of them wouldn't exercise it if it were present anyway.
And assuming Sony puts forth the effort to strengthen PSN to the level necessary to support the sort of massive cloud gaming they're talking about, then the only reason to be particularly upset about cloud gaming PS1-3 games is because you have shitty internet. Also assuming that Sony makes some sort of allowance for people who already own a particular game, of course.
But (and this is assuming that Sony wasn't talking out of its ass and actually follows through with most of the plans they were discussing last night), I weigh that against PC architecture that will allow developers to program for the PS4 without having to learn something completely different (which has been the case for the PS2 and PS3), the ability to stream games from the PS4 to the Vita and take it with you (I don't own a Vita of course, but I also don't particularly give a shit about mobile gaming as it exists currently. Being able to just play a PS4 game on a handheld, however? That I can see), being able to try functionally any game that comes out without having to buy it (take that, lame-ass piracy excuse #3), and all the other features discussed?
I still have my PS1-3, if I really want to play those games I can dig out the console necessary and have at it. And that assumes that Sony drops the ball on the streaming.
On the whole, I'd say it was a solid reveal. Yes, the only really specific hardware datum was the RAM specs, but if you expected a full rundown on the console's capabilities then you're moderately retarded; if Sony gave detailed system specs now, it gives Microsoft a chance to update their plans for the 720 before their own reveal. If you were expecting a price, then you're going full retard, for much the same reason.