So i'm trying to get my feet wet in media buys and am messing around with Adbrite. I set up a campaign that is targeting females in 3 very broad categories (home, parenting, shopping) with a max CPM of $1.50. So far this campaign has been running for 1 week and I have only got 35 banner impressions. Why is this so low? It my max bid of $1.50 to low? I actually though that would be kind of high for a CPM on such broad targeting. Or is Adbrite just crap for advertisers and should I look somewhere else?