I found that IE seems to crash or exhibit buggy behavior somewhat more under Jaguar than it did under 10.1. However, I'm having some issues with Jaguar in general -- namely, it's running slower on my iBook 500MHz than 10.1 did (go figure). However, I should not that IE has only crashed on Jaguar once (in a week) and perhaps crashed once or twice in several months of 10.1 use.