I'm planning to buy a digital camera in the US. Do prices go down after Thansgiving or the New Year?

Everything in America is on sale the day after Christmas (December 26th). There is also a ridiculous tradition of stores offering short term bargains the day after Thanksgiving to get you into the store. That would be this Friday, Thanksgiving in the US is on Thursday.

The best prices occur right after the Christmas holiday.

go on black friday, which is the day after thanksgiving, take a look at the cameras, and find out what deals they have, also yeah christmas time they do go down in price but look around. don't just buy when you see one. there are to many stores to buy from in the us