I e-mailed them and they got back to me within the hour. They told me I could return them for new ones if I wanted. They asked for digital photos in case I wanted to keep them. I think that shows an appropriate amount of concern for the their products and quality control.

I took the wheel I built with one of the rims to the LBS (I am blessed with a great LBS) and they think Velocity probably just ran out of "28 hole" decals and threw a "32 hole" on there. They also pointed out that it would be pretty pointless to fake Velocity rims and go through the expense of powder coating them (they're yellow!). So I think all is well. Besides, the hubs I got from them just won't stop spinning.

I'll definitely buy from them again -- Benscycle and Bikeman seem to have the best online prices.