I use palringo for yahoo and AIM. Also works with facebook chat. It has worked well for me. You can use it on pc or mobile. Would recommend trying it out.
Windows Live
Yahoo
Facebook
Google Talk
AIM
Myspace
ICQ
VZ (3 protocols)
Hyves
GaduGadu
Twitter
And Skype (from your droid, make skype calls over wifi)
Only wish it did XMPP and I'd be all set, might try to find another app that's as good but has XMPP also.