So, sometime last night Firefox alerted me to the available update, which turned out to be the FF3 release candidate. I downloaded it, and shortly after my router crapped out on me, so I restarted my computer (which I don't do often enough), and went to bed.
Fast forward to me getting home from school and deciding to launch the new Firefox install. It loaded in seconds, whereas the previous beta would sometimes take as much as 5-10 minutes to come up. I'm just really glad that whatever was doing that got sorted out somewhere in the update.