In a previous post, I was getting a couple of odd errors in FF 1.5.0.3 but not from IE7 beta2 whenever I would click on a contact and then try to delete another contact. I solved the errors by added a separate request object for deleting a contact. So now my little contact list uses multiple request objects. I figured that out by surfing the web (read: googling) and also by reading a book called Head Rush Ajax by Brett McLaughlin. It’s a pretty good beginner AJAX book that explains a lot of the basics, including a rough overview of DOM (which I needed).