Half Life 2 based its game play around physics.. sure there were other fun things like guns, random water jets and some ok characters, but its big thing was "Look! Physics!".. and, to my mind at least, that worked ok.
I see the same thing happening here with realistic water.. only this time (from the sounds of things at least.. hopefully I'm right) the 'extras' will be far more interesting.
Hell, there might even be some comedy (albeit dark) in the game. I read in X360 world magazine that you can attach explosives to rubber ducks and set them floating off around a corner in order to dispatch an unsuspecting enemy… that should be amusing, at least the first few times
Either way, I’m looking forward to this, definitely on my list of things to watch for.