NHL 09I know I complain about the quality of sports games on a regular basis (because much of the time, they suck), but I try to give credit as well, and EA Canada deserves much credit for the support they've given to NHL this year.
Even when it was initially released in September, NHL 09 was an excellent game. But one significant patch greatly imroved the gameplay, and now, over FIVE MONTHS after the game was released, another patch has been released (initially for the PS3, and scheduled for late next week for the 360 version).
This isn't a patch that changes wristband color or crap like that--it's a serious effort to improve the simulation aspect of the game, both single-player and online. You can see the patch notes here, but I am so impressed that this game continues to improve. Developers continue to be active on the forums as well.
It seems like there are two tiers of sports games in terms of quality, and the games in tier one have developers who care the most about the realism of their product.