I figure this is a good place to discuss this. Anyone who uses Project Wonderful probably noticed they just recently separated all bidding into four categories: America, Canada, Europe, and everywhere else. So basically, the ad with the winning bid for America will be shown for people browsing in America, while the ad with the winning bid for Canada will be shown for people browsing in Canada, etc.
You can bid for all four categories to keep things similar to before, but the difference is that now you have to maintain four bids instead of one. Obviously there are certain advertisers who could really benefit from this, but I'm not one of them. As a host for adspace, I certainly like getting revenue from four bids now instead of one, but as an advertiser who has no reason to exclude any region, I don't like to have to pay for four bids, and try to keep track of them all, for each ad. You'd think that the bids for each region would be about the same in sum as the bids used to be, but I'm not so sure this is the case. Especially considering how the bidding jumps from 1 cent to 10 cent increments once you surpass 10 cents, I have a feeling that the price of advertising could change distinctly. I'm not sure how exactly, and maybe it won't, but I don't know. I just thought it was worth discussing.