i once downloaded an OS that had a tabbed browser but i cant find it now. it was a couple of months ago and it crashed so i got rid of it. the browser was exactly like the standard BB browser except it had an "add tab" option when you pressed the BB button. i wish i could find it again now that im a little more knowledgeable on loading OS's.
That all being said, a couple users have noted issues specifically surrounding BlueTooth audio and HandsFree. There seems to be a problem maintaining both types of connections simultaneously whereas in 5.0.0.592, both profiles would remain connected.