Of course, one of those three that fail to work is my fav OpenBook... 
-dantheman
I don't use OpenBook anymore. More precisely, I don't use FF's builtin bookmark system much anymore.
To be sure, FF3's bookmark system is better than FF2's. Most of what OpenBook does are now built in, e.g. But there's one notable omission -- the "remember last folder" option, which is very typical of FF3's bookmark system -- good intention, half-hearted execution. I like, e.g., the new tagging system, but its usability lags far behind what most social bookmarking sites provide.
I've therefore reluctantly moved to a social bookmarking solution for my bookmarks, while waiting for FF3's bookmark system to mature, perhaps with helps from extensions.
FX3RC1 seems to chew up more on CPU than FX2 (with extensions compatibility check off, even more).-dantheman
Chewing up CPU? Hmmm, haven't noticed that so far. Though, again, I'm on nightly, not RC1.