Just updated my GNU Emacs to CVS HEAD, trying to ride on the bleeding edge for a while...
Installation was quite painless, but my makeinfo was too old so I needed to hack the Makefiles a bit to include --force.
I tried the new GTK+ 2.0 support but didn't like it, the plain X style looks better on my box (but then, my GTK is quite old and I don't have anti-aliasing).
Also tried the new debugger mode—gdba—it works nicely but I personally don't use debuggers that often.
After removing the tons of new font-locking which seem to appear in every new version again, I like it better than my old 21.2 one. If I now knew how to make info-mode not remove the heading underlinings, it would be perfect.
Especially cool is the reveal-mode that shows the text inside the "..." of invisible regions if the point is over it. It makes exploring (and editing!) outline files a joy.
NP: Manowar—Hand Of Doom