Debian, Ubuntu, and Gentoo use the same 2.3pre1 version, and neither uses a patch for memory leak nor do I see it mentioned in any open bugs related to it.
Doesn't mean that there is not a leak, I am just going to hold off on downgrading back to 2.2. I will open a window, surf a little, and leave it open the next few days while I am gone and see if I observe the same behavior.