Also, If I manually add myself back into the users table while the progress bar is flickering, the page resolves but doesn't log me in unless I hit login.  That sounds like its having trouble with new users specifically.

"Are you using impersonation and forms authentication and still not getting user profiles created? "

The account does not get created in either case (though I haven't regestered using forms).

"...are cookies enabled on your browsers?"

Yes. 

"Which solution isn't workable in your network environment?"

Using an AD account in a web.config.  I know it isn't supposed to display in the browser but we have had one instance on our network where it did.

"When you say it isn't unigue to the provider do you mean you had the problem with the old AD Provider or in situations when you weren't using the provider at all?"

With the old AD Provider.  Yes it is carried over IMHO.

I know I made some configuration change the last time and it went away.  I didn't like Impersonation the first time I tried it so removing that could have been what resolved it (though that doesn't work now)