Shell, not sure how high up this is but I have just done some testing and it seems to be that I cannot edit my signup using IE8 but I can if I use Chrome or Firefox - so its a compatibility thing with IE8 only.
I cant give any more help than that sorry!
I the meantime, for those who insist on using IE, running it in compatibility mode lets you edit.
There are more direct bugs at Firefox than IE currently - due to everyone moving to Firefox. I mix between quite a few but the majority I use IE because I have very limited sites I go to.
I mostly use Chrome unless I'm developing something, FF2 was awesome but 3 seems to have been slow and crap for most of it's life. Apparently FF4 is in beta and is supposed to be much quicker so fingers crossed for that!
I'd still not use IE though, I like rounded corners on buttons 
Conclusion: Chrome ftw unless you're trying to subscribe to WoW which doesn't work in it for some reason.
Bloody IE, I knew it would be everyone else's fault but mine
Will investigate, cheers
Disclaimer: None of the above should be taken as a sign of mutiny
"I just keep getting crabs" - Me