Maybe I'm missing something, but wouldn't simply running under valgrind be a really easy way to find lots of leaks? Granted, it only works under Linux, but I'm guessing most leaks in FF are cross-platform. Sure beats the author's suggestion of "re-invent a lot of tools that already exist".
After finding Firefox consuming over 1.2GB of RAM after leaving my browser and a couple tabs open overnight, I for one welcome any improvement in memory management. Of course who's to say that some rogue site was to blame for the rampant memory hogginess, but still, FF should not allow something like that.<p>Still love ya FF!!!