I had issues getting tabs to load in the background. I had to uninstall 3, install 2 and get it working the way I wanted and then install 3 over the top. After I did that everything was working fine.

I don't use the bookmark window, so I didn't realize there was an issue there, and I'm on a laptop, so the scroll wheel thing has never been an issue for me. The only issue I had was with tab behavior and I managed to get that to cooperate with me.

The only improvement I've noticed is that some pages didn't work in 2, which had me looking for an alternative, and so far they all work for me in 3.