There is a New Release section in the streaming category and they do have movies that just came out on DVD there - not the "blockbusters" like Avatar, and for good reason...
If they had those available, the servers and bandwidth required to suppoort the people that would want to stream it would be impossible to account for - they would have to setup scheduled timeslots for people to watch it just to make sure they could keep up with the demand.
I have Netflix streaming on the PS3, and my newer TV actually has an IP connection in with with a NetFlix app which is nice.
I'm fairly happy with it - you just have to have the right expectations...