They're rapidly changing, so probably not. Barry adds new things all the time, and changes functions of them, etc. In other words, I wouldn't call Mailman's MailList object (which is really what that file contains) a public API.
It might be that inverting the problem might be the right answer: Mailman 2.1 goes through an API for all "member"-type queries, and so perhaps storing the member info external to config.db via a new "member-adaptor" interface, so that TMDA could also access it through a stable interface, would be the right Mailman/TMDA integration answer? See MemberAdaptor.py and OldStyleMemberships.py.
(of course Barry will chime in too.)
Interesting, though; just trying out SpamAssassin, and while it's working fairly well right now, the concept of TMDA is interesting now that I've spent some brainpower on out-of-the-box ideas about spam filtering. It's not very obvious to me that I can use it, though, since I'm not in a position to change my first-line MTAs here at work, and I'd be willing to bet they don't forward the user-extension form of address.
Are the contents of a Mailman configuration "database" (config.db/config.pck) documented anywhere?
In particular, the various keys. Keys such as "members", "digest_members", and "owner" are obvious, but others aren't so. I can probably figure them out with some digging, but I'd like to have some sort of reference to point TMDA users to.
TMDA has recently been trained to grok MM config databases (see http://mla.libertine.org/tmda-workers/200201/msg00050.html).
Thanks.