Well, you have to remember that it's not just how long developers work on something, but how many people they have working on it. Team Ico is a relatively small team with 35 or so employees, if you compare that to something like Naughty Dog with 100+ you can see why they could take quite a while to finish up their game. I don't think Sony is going to make out like gang busters, but I doubt they'll lose much if any.
http://www.ps3center.net/news/5105/why-does-team-ico-take-so-long/
http://en.wikipedia.org/wiki/Naughty_Dog
@Galaki, the game has been played in front of media for a few magazines so it isn't as though the E3 stuff is the only thing that has been showed. Also depending on what you mean by pre-rendered I don't think you're even right on that end, unless you just mean it wasn't a demo played in front of the audience like Uncharted 3 then yes you are right, but again the game has been played in front of people so I doubt they'll change hardware.
...
