Dota 6.74 AI map is going to be the next version of AI series. It will be having the same changes which occurred in the official map. The AI development team has already started working on it. Moreover, PleaseBugMeNot blogged that DotA 6.73c AI has been skipped and Dota 6.74 AI is now focused instead. You can expect the new AI map in the near future.
Final Update (April 2, 2012):
DotA 6.74c AI v1.3 HOPE map is released.Update #1 - PBMN Blog - (14th March '12)
By looking at the changes made for 6.74 DotA release, we decided to jump directly to that release. All heroes Item Builds are done, the new item build system is in place and things looks like working smoothly. Well there maybe some unusual stuff going on from time to time.. but that`s considered normal. The new items system tries to mimic human behavior. Builds are being built by stages: starting, core, luxury stage. After core, AI picks up random luxury items... more variations. Cloud_str, Green, gaibo and Simple went to hell and back making that system working.
Well, release date is close... if nothing crucible happens after 6.74 porting of course. Stay tuned, wait is almost over.
As you can see, the work on the AI is almost done, they have completed structure, item builds and heroes. Dota 6.74 AI will soon be available here after its release. So, keep coming here to check the latest updates of Dota.
Dota 6.74b Map
Dota 6.75 Map