I just created this account so I could tell you how great eBuddy is.
I've been using a lot of different IM clients on my iPhone and android G1 phone. In my opinion eBuddy is the best for Android! I use Google Talk, AIM, Yahoo messenger, MSN, and Facebook, so I need an app that can connect to all of those networks. On my iPhone I was using Meebo, which was great. My experience with Meebo on android has been bad. I keep getting disconnected, and the messages from AOL keep saying I'm connected from another computer and press 1 to disconnect the others and keep this one active. Plus, Meebo randomly crashes. I was really disappointed with Meebo - it had been my favorite for IM on my PC/Mac and iPhone. But is just horrible on my G1.
I have not had any problems with eBuddy. It just works. All of my contacts in one place. It has some good customization options as well. And, like Meebo it has a web interface that you can use from any computer if needed.
If you only use Google Talk, just use the built in app. If you use multiple IM connections, definitely check out eBuddy.