one thing can be memory leaks.
you should be able to see that easyly by looking at the mem the
browser consumes and see if that increases over time.

I don't have links on hand but a google search for html memory leaks
and closures should pop up enough info. there is a neat tool for IE
called drip one can use to check for leaks.


the next thing could be that you have too many requests hanging.
e.g. if you initiate a request every 750ms no matter if prev.
req. have finished. This could leasd to a build up of unanswered
requests. Not sure though if that would have any effect.
When you do a request make sure to set the timeout for the next one
iisode the callback for the current one. this will make sure you only
have one open req.

Instead of polling every 750ms, you can use a hangign get.
i.e. unless something changes or a timeout has been reached the server
will just wait with answering the req. This will lower the number of
req. made to the server but may have other implications as the
connection stays open for quite some time depending on the timeout.


That's my initial thoughts

Jan