No HD Ads?

Since my wife and I picked up a HD tv at the beginning of the year and started watching most of our primetime shows in HD I’ve found it interesting that the uptake in ads in HD is incredibly low. HD, when done right, has an incredible wow factor and since just getting someones attention is one of the primary hurdles of advertising why are they passing it up? With all of the stories of people watching sporting events that they didn’t even care about because the picture was so amazing it seems odd that advertisers aren’t jumping all over it.