Just installed it. Oddly, it imported the few IE bookmarks, but not the FF ones. There's a bite in the ass.
Also, looking over the plugins, seriously.... there's ones you have to pay for? No thanks.
I also have my Start bar to auto hide, which Safari likes to not show by being on top all the time in fullscreen. Other then that, I do enjoy it.
Will it replace FF? Not yet for me.