I have found that ebay has consistently paid more than adsense on my Hubpages and on my personal website, which is about classic arcade and video games.
I think the subject of your writing will dictate if ebay is a success - my content focuses on very collectible items, which often feature on ebay, and therefore my audience is more inclined to select auctions which are featured as part of my article.
If for example my article is on a specific and rare video game, the ebay auctions listed will feature that game. I may not get a huge number of visitors to the page, but they will be much more likely to click on the auction and generate revenue.
In contrast, an Adsense advertisement will only loosely relate to the content, and sometimes not at all, and is much less likely to generate a response from the reader than a targeted ebay auction for this kind of article.
For other blogs that I write that feature product reviews for currently retailed products, I will use Amazon which has a great return for this kind of article.
You have to pitch the revenue generation technique at the article in question, and always ask yourself why someone would be reading your content, what would have lead them to the page, and how likely are they to want to engage with the advertisement.