Your store categories are displaying in alphabetical order to me, I've attached a screen shot just so you can see how it comes up (I looked with 2 different IDs and it was the same order each time). (Edited to add - the only exception is "Other" which is always last because it's an eBay default category for "everything else" after your main categories).
You can re-order the categories very easily if you ever need to, though - when you go to 'manage my store' and then click 'Store categories', up the top on the right (just above the add category button) is the link to re-order them manually.
