AJAX app (Google maps), back button, and unique urls

I’m working on a page that uses Google Maps, and started implementing unique urls and back button compatibility using window.location.hash updating whenever an interaction with the map occurs. (See http://ajaxpatterns.org/Unique_URLs for more info).

However, I’m now thinking that this might not be such a good idea. Personally, if I go on a page using Google Maps, I expect the back button to take me back to the page I was on previously instead of back to the last thing I did on the map.

If I remove the back button compatibility, it would mean that the url is not automatically updated with each interaction. Instead I’d have to add a button that the user can click to get the unique url to the map in its current state.

What do you think about recording every interaction with an AJAX app like Google maps in the browser’s history, good idea, bad idea, or neutral?