On a number of boards, especially CreditBoards, people are reporting changes (some of them huge changes) in their TransUnion reports.
Specificially:
1) Old accounts gone. I lost half of my tradelines.
2) Old deleted accounts reinserted, especially derogatory accounts.
3) Existing accounts reporting in newly wrong ways (such as included in bankruptcy when the person had never filed bankruptcy).
4) Other people's files mixed in with theirs.
On the up side, it looks like they've added some other things, like updating creditor names and so on.
Anyhow, I encourage y'all to check your TransUnion report by the means of your choice (though I'm sure our sponsors would like you to pull your FICO report) just to double-check that everything's hunky dory.
For me, my FICO went up 8 points, but others have reported 100 point losses.