I did finally get around to trying a game online tonight. As it turned out there was one guy in the game lobby and we were able to get in a full nine inning game; a game I ended up losing 7-1, cementing my rep as the most incompetent sports gamer ever. (I didn't have my headset on so I wasn't able to communicate with the unfortunate soul who had to face my mad skillz.)
With regards to the score... To be fair, I feel there were mitigating circumstances.
Online play was a nightmare in 2k8 last year. It is better in 2k9. It is not, however, good. Granted we're talking small sample size here so bear that in mind. You can ID pitches for balls and strikes this year before you're committed to swinging the bat, which is a desperately needed improvement. But the window for doing so is very small and the timing for hitting a pitch is very different from hitting offline. For me it was like learning to hit all over again.
As for fielding... look I'm struggling with the fielding as it is because -IMO- it's just wonky. But I have been adjusting such that I'm not misplaying nearly as many balls as I was in my first few games. Online, though, the game's on again off again hitches and stutters made it very hard for me to field the ball. I'd say 3-5 of my opponent's runs came as a direct result of my "misplaying" the ball. Now, my opponent only had one obvious case of this happening to him, so you have to factor in the notion that maybe I just suck at it. Nevertheless, I don't have this problem in other sports games, so I'm not giving 2k a free pass with this because I think it takes a chunk of the fun out.
Will I be playing this game online after my review is done? Absolutely not. But if you're a 360 gamer and you want to play online, I think you'll be able to get much more out of the game than last year, so that's something at least. (Does anyone remember if they patched 2k8 to make it playable online? All I remember is that it was flat out busted pre-patch.)