"The outlooks on the large financial institutions sector in the U.S. are now predominantly negative," the credit rating agency said in a statement, noting the potential for more write-offs from the sector. There were also a few shake-ups on the executive floor. Wachovia announced that it has ousted CEO Ken Thompson, who has come under fire as the fourth-largest U.S. bank suffered through a series of credit-related problems. Wachovia said Chairman Lanty Smith will serve as interim CEO until a successor is found.