I've been wondering about this, too, although I suspect there would be little tolerance at the Fed and among other big players for attacks on JPM. Going after little old Long-Term Capital Management is one thing, but going after JPM is quite another. It is noteworthy, though, that there have been a few recent instances where the analysts have "broken ranks" on JPM: S&P with its repeated threats to downgrade JPM, Lehman (I think) with a downgrade shortly after the July Congressional debacle related to Enron.
Another one to watch for signs of collapse is FBF: they were out yesterday indicating that their dividend is at risk if they run into problems with their heavy exposure to Brazil. They're assuming that Brazil has restabilized and will present no unexpected problems--. LOL! FBF has already suffered massive write-offs in Argentina and is desperately looking to unwind additional Latin American risk. I'd look for attacks on their positions over the next two or three months, with particular event-risk surrounding the Brazilian elections next month.