I had given up on Firefox on my ibook because it was too slow and used so many resources that multitasking was nearly impossible, but I just downloaded FF3 last night and it is much faster. I had been getting used to Safari but missing FF, but maybe I can go back now. Most of the plugins have not updated yet, but I imagine they will at some point soon. The editor in WordPress works, the look is pretty slick, and it has this thing where when you type into the address bar a pulldown-type window pops up with suggestions.
