Just launched ads on our mobile site. On regular site, almost all ads are 728x90 and that's what I created for the mobile site. But is that the best way to handle this? I WANT the rectangular design, but 728x90 maybe is not meant for a mobile site. Appreciate a better size for mobile site.
Besides, you could or should consider gif, jpgs or text ads. I'm considering it because traffic from opera mini doesn't show Google Ads and I've been reading very good theories on "they never will". So if you have lots of mobile traffic with that user agent, take it in count.