Ad weight is a concept specific to the text ads (the block that appears below the game image on game pages).
When a user looks at a game page, we select one ad at random from the advertisers who have targeted the page. If all advertisers have the same weight, then all advertisers have an equal chance of having their ad display.
However, if one (or more) advertisers have paid to increase their ad weight, their ads are more likely to appear than the other advertisers, by a factor determined by the weight.
For example, if one advertiser has a weight of 3, and three others have a weight of 1 each, that advertiser's ad is three times as likely to appear as any one other advertiser's ad. Because the total weight of ads is 6, the advertiser with weight 3 will have their ad displayed on 50% of the pages. The rest of the advertisers will divide the remaining impressions equally.
Ad weight is determined by advertiser--if you pay for an increased ad weight, it applied to all of your ads!
Ad weight is available in any amount, as long as the minimum ad buy is paid for. Talk to Chad (email@example.com) for details!