According to the Gaim Web site, the project has held off on non-beta releases because of an ongoing trademark dispute with AOL over the name of the project:
A few years later AOL trademarked "AIM," and started referring to their IM services using that name. They complained. The issue was brought up on Slashdot, and the Gaim developers at the time got some legal support. That legal support advised that the ongoing discussions with AOL be kept confidential until fully settled, and so it remained. The public thought the issue had gone away then. It sorta did, in that AOL stopped responding to Gaim's legal support for a while.
Our legal support has changed several times, and each group of lawyers have recommended silence & secrecy. Around the time of Gaim's first 2.0.0 beta, AOL came back into our lives in a very strong way, this time threatening to sue Sean.
This represents a clear pattern. AOL received more pushback than they expected, and would sort of let things stand for a while. Then they would threaten a different Gaim developer. Each time a new Gaim developer was threatened, we had to look at new legal support, to prevent a conflict of interest.
This process could not go on forever. As a result we ended up forming the Instant Messaging Freedom Corporation, and making it legally responsible for Gaim. We also had our new legal support work to create a real settlement with AOL that would get this issue dismissed from our lives forever.
Getting a settlement with AOL has taken FAR FAR longer than we would have ever guessed. On legal advice, we have refrained from any non-beta release during this process as a show of good faith, and to keep AOL from giving up on it. Again, on legal advice, we have also kept this information closely controlled.
The name the team settled on is Pidgin for the Gaim client itself, "libpurple" for the libgaim library that is also used by other projects (like Adium), and Finch for the Gaim textmode client, gaim-text.
The Gaim team is also moving to Pidgin.im, and using their own server instead of SourceForge.net to track development -- though releases will still be distributed via SourceForge.net's mirror system.
According to the post, a Pidgin 2.0 final release should be available sometime in the next week.