but if you dont run just uk based site then its worth signing up for the u.s. one too and offering links to both sites...
its also a cool way to get up to 15% off any books you want to buy (well in sorts think of it more as a rebate...) which coupled with a new account in your dogs name to give you your first ã3/ã5 off makes it nice and cheap and cancels out the horrible p&p charges...