I have one very frustrating issue that comes up day to day, i would have 0 orders in pack, and all in pick and it just so happens that i got a good day and just have to move everything to pack, the problem... The menu doesn't show the pack option after the initial change (because of the menu being loaded before the change had been committed) which means a secondary refresh would be needed. Now although this doesn't sound like much other uses for a AJAX style menu would be that your menu numbers in pick pack or errors etc update without a refresh needed on the page.
This sort of change could be done cheaply and simply (the bad way) of just moving the cost for the menu to a seperate file and using Javascript to load the page into where the menu is periodically but i think it should be done for individual items such as when you hover over sales orders the old values will be displayed but a loading icon will appear and then the values will be updated when the data is loaded.
