My copy arrived this morning and I went home on my lunch break to give it a quick bash.
I had a good 45 minute run and in this time I managed to create my character, map my face on, customize the dudes armour and arsenal and play through the 1st mission. I can say I'm very impressed.
One of the new features which I didn't read about is being able to direct your team mates to throw grenages/flashbangs where you want them during firefights, not just when entering rooms which I think is a welcome addition. This means that you don't have to rely on your own stock to take out enemys (though from what I can tell doing this doesn't add to your ACES).
But so far my 1st impressions are that of a grinning maniac with an itchy trigger finger... now I'ev gotta wait 4 hours till I can play again