I assume that if the Zone interface breaks under IE 7, that'd be the first thing you mention, but I ought to ask to be sure. I haven't installed the IE7 beta because IE installations always nuke the previous version, so I'd lose the ability to test my designs against the mainstream version. And I probably won't upgrade until at least a majority of users have, to avoid the trap of designing sites that work in 7 but break in 6.

It's been a good four-or-so years with a stable browser environment, but I knew it wouldn't last forever. There will be problems, but it's good that (apparently) there are no problems yet.