Yes, I never noticed it before and very useful it is too.
I have just installed it, lost several add-ons that weren't security related so no issue. I have just hacked the xpi file in three of those add-ons so I can continue to use them. I also lost all but one of my Themes.
I haven't had a good look round it to see the new features, but page loads do seem to be much faster, important on dial-up.