They abandoned YM around version 2.5, and this 3.0 beta thing's been going on for almost 2 years. But at least when you compare it to the original 3.0 beta, it's made some progress. There's audio AND video, and can make calls, supports SMS (in some countries) and mobile devices.

Which could not be said for MSN (seriously, no significant new features since version 3.0, or even earlier!?) or AIM, the latter of which has only just been picked back up and still doesn't replicate the feature list of even the 5 year old version 4.7; it took Apple to give Mac users any kind of AIM advancement. And let us not even speak of ICQ; we're approaching 6 years of abandonment - nuff said.

In recent versions I've noticed it's stopped crashing every time I log out or quit, so that's some progress.

So, it may be damning YM with faint praise, but of the major official IM service clients, YM is at least conscious, while the others are in comas or, in ICQ's case, rotting in a drawer in the morgue.