I had intended on writing a long blog post with screenshots and everything explaining some of the new features, and changes, in the upcoming Joomla 1.6.
But I'm lazy and I don't see any point in re-inventing the wheel so just take a few moments to read this excellent presentation from Andrew Eddie.
I'm still not convinced that the core of Joomla needs the bloat of tags and comments but only time will tell on that one. (I originaly came to mambo because I was looking for an open source application to build dynamic web sites that did NOT have comments)