Regional Banks

I'm hearing, from semi-reliable sources, that regional banks are going to have problems over the next six months, some may fail due to the sub-prime loan mess; and the feds won't step in and prop up these medium sized banks. I have two questions: how can you figure out whether your bank has been making foolish loans and is at risk? And, how does a bank failing affect that bank's non-mortgage depositors and borrowers? Thoughts?