I've applied a grad program at the wee state university I attend as an undergrad. The super nice lady in the grad school office checked some incorrect stuff on my boxes on her end of the online application and scared the heck out of me.
Luckily it IS a wee state university and I stopped by and straightened it out. Don't think I'd have that opportunity at a larger school out of town!
YMMV, but if I had an actual acceptance communication in hand - I wouldn't worry.