Vumba: aMSN 0.95 is a stable release of aMSN
the CVS-version is sort of a developpement-version, it has new things, but is still a little bit experimental. If you use CVS, some things MIGHT not work 100%.
However, I am using CVS on Ubuntu (and Windows) all the time, I find it very stable considering it is supposed to be a test-version.
1) On Ubuntuforums.org, someone has written a script which downloads and installs latest CVS for you
2) If you really want the use the latest and newest of it all (tk8.5, tcl8.5,...) :
I would recommend the first option (1)