Well it took me about 20 hours to platinum UC2 , I'm hoping at least 30 to platinum UC4.

I hope at least 20h

If I'm going for a platinum trophy, which I probably will as long as online MP is just play one MP match, or they are all only bonus trophies, then I can see putting in 30 hours to get there. I expect 18-20 hrs for the first play through (on hard), and probably not much less for a second playthrough on insanity (or whatever they end up calling it) given I'll die a lot and have to replay some sections multiple times. And that assumes I manage to collect all treasures on just those plays. ther

good, 3 was shorter than two

Maybe this one will push 10 hours

All of the Uncharteds were pretty short (about 12 hours each for me, with Uncharted 2 clocking slightly longer). The Last of Us was much longer (~23 hours for me). I think part of it was that TLOU so heavily encouraged exploration that the game felt much longer.

I was very satisfied with TLOU's longer runtime. I hope Uncharted 4 follows a similar approach.

A bit longer than Uncharted 2 with the same amount of quality sequences and a more mature story would be perfect. Damn this game is going to be so fucking good, greatness finally arrives.

More content, the better.