Unsecured creditors include other financial institutions. Banks (hell, even the biggest credit unions may participate here) lend reserves to each other overnight so that they meet requirements. Inter-bank lending to WaMu has slowed dramatically. In other words, the other banks don't trust WaMu.
WaMu's own unsecured creditors (the people WaMu owes money to, aside from insured depositors) are the ones pulling money, not folks who owe WaMu money.
Actually that's the point I was trying to make...your post, of course, makes it better, thanks. My MAJOR concern is that a little 4 analyst outfit called Gimme Credit is the outfit that started the rumor that 'unsecured creditors are pulling money out' at exactly the same time that FHLB, et al became huge 'unsecured creditors'. My gut feel tells me that Gimme Credit is either related to the Hollywood (film) Company of the same name, or just another Short 'consultant'/basher/rumor mill available for hire to 'help' the naked short 'investors'./rant