I think that most problem that financial industry will face is that they already have/invested in an Appserver namely like Websphere and Weblogic. And most of them already have JDK 1.4 installed. This is a challenge because most of them don't want to replace their existing appserver and the JDK becaus Seam will require JSE 1.5 and JEE 5 to get it running. Other than that Seam is quite stable though it still has some minor bugs here and there.
I suggest you contact sales at Redhat/JBoss. I know there are financial institutions using Seam because I just got back from a week of training/consulting for a reasonable sized bank implementing multiple internal applications in Seam. I'm pretty sure I'm not allowed to discuss Red Hat customers in a public forum, but I bet someone in sales could provide a reference.
Hi all - thanks for the feedback - I'll try the sales team!