At the moment AuctionAds is giving you a 100% cut while they build up members. But that's not the point.
eBay gives you higher percentages depending on how much volume you push. The top tier is 75% (
see here). Chances are, you aren't going to generate $3 million in revenue. That's where AuctionAds comes in. When you convert a sale through them, it adds on to one HUGE eBay affiliate account. Since every AuctionAds publisher contributes, getting into the top tier is very easy.
So you see? You are getting a 75% commission now, instead of 50%, because you used AuctionAds. And as I said, you get 100% of that at the moment, though eventually AuctionAds will start taking small cuts.
So presuming you aren't pushing $3,000,000 worth of sales, AuctionAds is great. You make more money than you normally would, AuctionAds (will soon) get a cut, and eBay gets more affiliates than they would otherwise, since they're encourages by the 75% conversion rate. It's a win-win-win situation!