A good note on the state of browser support for DOM …
This is a good article on some of the various differences in implimentations of DOM is the various browsers. Good info to know if you are developing JavaScript on the bleeding edge …

Waiting for the DOM. Though great strides have been made towards the ultimate goal of a single DOM for all browsers, some implementation differences still remain. Guest author Kenneth Tibbetts provides some browser-specific scripting gotchas to watch out for. From the WebReference Update. 0315 [WebReference News]