I've implemented my own Movable Type Integration. This thread will serve as a listing of concerns or bugs until I can get it to the point where it is publishable.

1) Need a small form in the MT Templates to post a response. It should populate the vB Reply form for the appropriate thread.

vB requires a CAPTCHA to preview if you are not logged in, so I either need to just deal with that or hack VB.

2) I need a flag on individual posts which should be added as content to the article page. I'd rather not recreate the entire thread in the article page, but some posts are interesting, informative, or whatever and should be repeated.

3) Sessions are abandoned, which potentially creates a problem maybe (see how I'm all wishy washy on this issue). What I really should do is store the cookie jar and not re-log in if the session is not expired.

4) Reason for update should be specific about whether it's a link update or a textual update.

The status of all of this tonight is -

Creating new threads and editing threads works just dandy.

I seem to be able to build any one particular post, but if I rebuild several that do not actually have threads already created, I get errors. OTOH - once the threads are created, rebuilding en masse seems fine. Perhaps the cookie jar thing noted above will resolve it.

I have a plan for moving existing comments, but I haven't begun to build it.

This is definitely getting to the point where I'm comfortable using it, but I definitely can't publish it until mass rebuilds don't cause problems.

I did look into just throwing a quickie form on the article page and it doesn't look like that's going to work out very well. I'll have to explore more complex options.

I've split out the vb Login function separately and have cookies set up to be maintained in a file. This should speed things up considerably on initial setup because it will reduce the number of web page posts, although this is far from an optimized implementation.

As it turns out, multiple login sessions in quick succession was not the problem associated with mass entry rebuilds. The problem is that I had flood checking enabled. In order to do a rebuild of multiple entries without existing discussion threads, you have to temporarily disable flood checking, or perhaps you could install a plugin/hack that disabled flood checking for the MT Integration user in particular (or ideally with any automation routine).

I'm still a little bit perplexed as to how to handle commenting directly from the article page - the problem really in being how to handle the differences between logged in users vs. anonymous users. I don't want to turn each article page into a php file and I don't want to include a set of overly cumbersome HyperText Meta Language or javascript. I'll have to poke around vBulletin.org to see if somebody has already resolved this problem for a similar integration.

This is going to be interesting. After thinking about it for a while, I think a three-click interface for anonymous posters is a good thing. For registered users having a one-click reply method would actually simplify things a bit for me. I can test for a login cookie and kick out a reply box via javascript pretty easily.

I actually attempted to rebuild my entire blog, while I wrote this post, so we'll see if everything gets generated appropriately. Here's to hoping. The rebuild process has definitely slowed down significantly, but that's mostly because of the one time thread creation thing.

Update: Looks like all the threads were generated. Now on to migrating existing comments into the new interface.