Why aren't ads in widescreen yet?

So I'm getting a widescreen TV soon and I'm wondering why the heck advertisers and their agencies aren't producing ads in widescreen? Want to do it in 4:3? Pan and Scan to make a cut. Consider that for the next 4 years until all the stations are forced to be 16:9 HDTV, so why not start converting advertisers over to filming in 16:9 1080i video now? You already film in 16:9 for ads shown in the theaters (of which I've seen a 4,374% increase in lately). Sure, I'm not the typical viewer, but damnit, I like advertising in widescreen along with my favorite shows. Comments? Some links of interest:

• ITC Revises Widescreen Opinion
• Austrailia Begins 16:9 Digital Broadcasts in 2001
  

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