Sounds like it's a good step up from 3 in many areas, though probably would still leave something to be desired if you had to compare it to the first two games.
If anything, might want to wait for the reviews on the upcoming Sigma 3 on ps3 / 360 - chances are that will be the 'definitive' version of the third game. Unless they're gonna release it FOUR times, which even by Team Ninja's standards is getting a little nutty. :P
"The act of treachery is an art, but the traitor himself is a piece of ****." - Mike Tyson