I don't know what game Gamespot played but this game is a "9".
The soundtrack is much better than lasts years horrible "Daddy Yankee" esque mix. I know that it has a decent sized following now but its still not mainstream enough to have so many songs from that genre. You're going to get complaints when you make a soundtrack mostly rap, so making it a sub-genre is going to disappoint even more fans. None the less, this years soundtrack fits better in the background. Its not phenomenal at all but its not a collection of annoyance.
They made the A.I much smarter and made it easier to counter haymakers. The problem with last years version is that the A.I. was inept in countering someone who was comfortable with haymakers. They also gave you control over haymakers to the point where you can instantly decrease an opponents health (A.I does this enough to keep fights interesting) and to go to a first person view of yourself punching your opponent. While the latter may not work well on the CPU (haven't really tested it on the cpu to be sure) but I can see how it would bewilder a human opponent.
The pre game TV you see on your career menu is very cool. Before you schedule fights you may see a higher ranked fighter calling you out. This goes on until you reach their rank and fight them. If someones not calling you out then you'll see something about yourself flashing across. Every victory will flash across the screen as well. Its something small and silly but it does add to the value of the fight.
Not only can you choose between Fast, Balanced, and Power stances, but now you can shoose two additional stances from the start including Mummy and Wild. To add to this you can choose you style of punching (Speed, Balanced, Power, Slugger, Uppercuts, etc) and your style of blocking (Cross, Basic). In short if you find a human player online or a friend brings over a save with is fighter to your house, you should be seeing much more differentiated and customized characters.
The announcer also has been improved upon further.
Knockdowns? The sounds and the close-ups sometimes make me wince. I've held my sides multiple times after dropping some individuals from deadly body shots. They got rid of the instead siezure that players would have and instead have they fall down from head shots, and fall to their knees from body shots. While this will dissapoint fans that enjoyed unleashing flurries of punches on stunned opponents, this is much more realistic and you can still get off 1 maybe 2 punches on a falling opponent.
Fan of boxing? Buy this. Nuff said.