This is a phenomenal game. Absolutely loving it so far.
I know when I am really enjoying a game, because I replay all the set pieces over and over again. The only other games I can remember doing this with were Max Payne 1 and 2, HL1, HL2 + Episodes, Outlaws (very old), and the original Fear demo.
For those worried about the change in setting, don't be. It works perfectly. Plus you get to shoot some Jersey Shore guido douchebags in the face!
Makes my PC very very toasty and warm though.
Can run all high/very high, no AA at 1680x1050 perfectly fine, with only some slowdown at very few very hectic places.
PC is:
i5 2500K (stock)
ATI 5850 (stock)
8GB Corsair Vengeance
Love it! Well worth £30. Took 7 hours to download on steam with Sky internet at around 1.1MB/s