This week I am going to try to write a plugin for the shoemoney eBay ad system for wordpress. We have gotten pretty good feedback so far about payouts so looking into developing it a bit further.
In order to get this to work you must have a shoemoneyads account (its invite only but we let in about 500 new people a week. We just have to keep it moderated so we can expand hardware wise as needed and existing publishers do not have downtime)
Also you must have a comission junction account and also have applied and been accepted to the ebay.com program.
Keep in mind the program is still beta and I would not recomend it to websites that are already going really well with adsense/ypn. It seems to work better on niche websites.
If you want to play a bit to see what kind of ads would show up on your site you can use the shoemoney eBay ads sandbox tool