Customise the order your posts are display in using this simple drag-and-drop Ajax interface.
If you have any questions or comments, please drop me an email: http://joelstarnes.co.uk/contact/
Try opening up your WP admin and browse to your postMash page, then take a look at the page source. Check if the prototype or scriptaculous scripts are included in the header. If so then the next step is to track down the offending plugin, which you can do by disabling each of your plugins in turn and checking when the scripts are no longer included.
Nope, not any more.
Any good up-to-date browser should work fine. I test in Firefox, IE7, Safari and Opera.