Ryan, I'm really pretty disappointed in the forum announcement. Most of the mods received emails yesterday with their passwords included in clear text. How can the board management state that they have no indication passwords were revealed? Getting a dozen of them in email is a pretty clear indication. Further, unless you have customized vbulletin the passwords are not encrypted, they are hashed using the very weak md5 algorithm.
Bottom line: you have to consider the entire password database has been revealed and you should have forced a site-wide reset. The weak advice in the announcement does your users a disservice. As I reported to you yesterday an old PayPal account of mine that used the same creds as my account here was intruded into from China Tuesday evening, before I proactively changed the creds. I didn't even realize AT was the source until I received my own copy of the warning email with my own email address and forum password included.
This is not the right way to handle something like this, at all.