If you're talking about AIM, then Tony said at one point he aims to get all possible versions and protocols working at launch, but in alpha it'll just be 1.0 - 6.2 and beta will include versions 7 and 8.
AOL to my knowledge is not Tony's priority for launch platforms. It's mostly been focused on AIM and that'll be the one platform guaranteed to be supported at launch. And AFAIK there won't be any sort of beta test for AOL, and if there is it'll most likely be private like with the beta testing for AIM (which before you ask isn't accepting any more testers) and testers will be comprised of people Tony can trust to report constructive feedback back to him and not just clown around on the service for a bit and fawn over how "nostalgic" it is. That's the impression I get when people constantly ask for beta testing periods for this stuff anyway.
That being said, from what I've been able to understand Tony's focus for AOL is getting 4.0 to work, so once AOL support is first released I expect that'll be the most predominant version in use. He also stated versions 2 - 3 might be supported at launch but don't count on that so much.
I'm sure that once NINA is out of beta it'll support that version and versions before and after it. The end goal of the project is to support as many platforms that support the AIM and AOL services as possible, conventional or otherwise, along with many other services after its official final launch.
(I personally believe this information should be stickied in a thread of its own to get people to stop asking these questions BTW)