Trillian 4: Sneak Preview
I've never installed AIM on any computer I've had any control over. I've cringed when people think the protocol and the client are one-and-the-same. I always encourage people to install alternate clients, and poke fun at those who don't.
Trillian was the first IM client I ever used. It proved to be solid even at version 1.0. I stuck with the free version through 2.0, demoed the Pro (for-pay) edition during the development and release of version 3, and eventually decided to buy it. After version 3's release, I started growing annoyed with Trillian. I started doing more work on other platforms, and experimenting with other software. Trillian's bloat, and Windows-only state simply couldn't compete with Miranda's speed (and portability), Gaim's cross-platform compatibility (and portability), or Adium's beautiful eye-candy.
But I've always maintained a shred of Trillian loyalty, and kept track of Cerulean Studios through their very slow release cycles and sparse blog updates. And now, after entirely too long, they've released a bunch of information on the forthcoming 4.0 release of Trillian (and concurrent web services). The first-look is exciting, and is impressive enough to make me feel inclined to try it out again. If the Trillian dudes come through with their promises, this software might just be a worth a serious look again.
More information and eye-candy can be found at the related blog post and preview site.