How can I determine if a dynamically-created DOM element has been added to the DOM?

According to spec, only the BODY and FRAMESET elements provide an "onload" event to attach to, but I would like to know when a dynamically-created DOM element has been added to the DOM in JavaScript.

The super-naive heuristics I am currently using, which work, are as follows:

• Traverse the parentNode property of the element back until I find the ultimate ancestor (i.e. parentNode.parentNode.parentNode.etc until parentNode is null)
  
  
• If the ultimate ancestor has a defined, non-null body property
  
  
  • assume the element in question is part of the dom
• else
  
  
  • repeat these steps again in 100 milliseconds

What I am after is either confirmation that what I am doing is sufficient (again, it is working in both IE7 and FF3) or a better solution that, for whatever reason, I have been completely oblivious to; perhaps other properties I should be checking, etc.

EDIT: I want a browser-agnostic way of doing this, I don't live in a one-browser world, unfortunately; that said, browser-specific information is appreciated, but please note which browser you know that it does work in. Thanks!