If you are talking about the Chase Disney Visa Card, then awesome!
The Character Meet n' Greet is in California Adventure at Ariels Grotto (downstairs). Between 10 and 11am. You show the person at the stand outside your visa card and he or she lets you go down stairs.
The characters (at least during our trip in September were eitehr Chip and Dale or Mickey and Goofy.) are hanging out, waiting, you snap a few photos, and the photo lady gives you your photo claim tickets as well as a 'free photo voucher' then you are entitled too, (as a disney visa card carrier!) There was NO wait what-so-ever. We walked in, took our pictures (she took a couple since her camera was acting up) and we left with the standard, in about 3 hours pick it up from the 'Greetings from California' photo center ^_^
I felt very special to go home with a photo with Mickey and Goofy (and not have to wait an hour to be told, 'Mickey has to go now!!') This was the ONLY time we had seen either of these characters and been close enough to get a photo (much less a official disney photo... for free!)
hope this answered your question
