I write all my web apps on Cobol, with formal specifications for every piece of code. This Java/.NET/javascript/Rails/Python thing is just a fad. Everyone will come round back to Cobol, wait and see. Mark my words...
Makes you wonder if all the people dismissing everything as 'fads' even have jobs. Because I can't imagine anybody hiring someone in IT who is so proud to dismiss any new technologies not on merit but because it is somehow fashionable.
We don't rip off the majestic buildings of Manhattans because they are more than 50 years old. We preserve the buildings that survive the test of time and demolish the ones that don't.
It's the same principle here. The COBOL system that is existing right now is the survivor of brutal business changes in the past 40 years. You don't kill a survivor - you maintain and enhance it.