Of course, EA wasn't real happy with all the speculation, but they didn't actually deny anything. And as DB points out, the investor document didn't say that XP wouldn't be supported, it only specified Vista and OS X.
But still, if you told me earlier this year that Battlefield 3 would be released on OS X and not XP, I would have laughed in your face. If EA really is planning to bring out a top tier, anticipated title like this simultaneously on OS X, they might be able to redeem themselves to Mac gamers yet. Sure, I'm still angry at them for buying out BioWare, but brand new games on the Mac is good for everyone.