I have the latest 17" MacBook Pro, 2.2ghz stock and I've only tested this with OS X. When the power is being pushed, the battery status will report that it's no longer charging and the battery will be used and will slowly lose spend its charge. If it's fully charged, it will slowly lose its charge even if the power is connected. This occurred when playing Starcraft 2, World of Warcraft, streaming with FlashLiveMediaEncoder, running intensive WebGL applications. I have attempted to resolve this issue by reinstalling OS X, resetting the PRAM and SMU, I had the MacBook Pro exchanged for a new one and it also exhibits the same issue. Did I draw two unlucky straws? I haven't seen any other reports of this issue.