Watch out, your 1.1 MSDN local documentation gets wrecked by IE 7 - the style sheets no longer render so you get Javadoc (urghh) style documentation.

I also had tonnes of problems with our internal network with IE7, it wasn't resolving server names for some reason (a rollback to IE6 solved it).

Also IE no longer waits indefinitely for a server reply when debugging an ASP.NET page. I tried this in .NET 2 and you get an error message from IE 7 after about 20 seconds.