I tried the updated (EOS Utllity) in hopes that it would cure the odd connection routine that is required with a 5D on a Leopard system. It changed nothing. Works exactly as before... perfectly reliable except for the strange set of connection steps (must have camera menu on when connecting, wait for the error message in EOS Utility, then clear the Menu) that weren't necessary on Tiger systems.
I installed the update today on my Mac. It seems to be working fine. The raw conversions look great. It's still one of my favorite raw conversion apps when it works.