I'm having a problem where I have started several splinter sites off of my main site (different niches, same CMS and Layout) and the ads on the splinter sites are targetted to the original niche. Could this be because I didn't change the channel names on the splinter site? Eg on the main site I had homepage-top-left homepage-bottom-left homepage-middle-right content-top content-left content-bottom And just left them the same because the ads are served by the CMS and are in the same position on both layouts (I set up URL channels as well). I figured with the new content the Adsense would adjust.. Have you guys ever heard of this happening?
You might need to work on keywords for each page. If you have images with terms in them this can make ads show for those terms also.
I suppose they are similar niches.. the advertisers could very well be targetting both. But my keywords are definitely distinct between the sites and the articles definitely cover different things. I am pretty sure this isn't the problem because they both rank well for their respective keywords.