I may be mistaken, so someone correct me if I'm wrong, but I'm fairly certain that AJ incorporates new websites and (maybe new content from sites already in the index) at least three months later, as if there's a quarterly update. This may have changed, but I haven't heard about it.
Could be the topic matter. Some topics don't feature ten AdWords ads above the fold.
They've recently backtracked and promised to reduce that amount to seven ads above the fold, but that's still too many. They show more ads on top than Yahoo. Even MSN shows only three ads on top. MSN says too many ads degrades the user experience.
I have to add that showing that many ads on top makes AJ irrelevant to many webmasters because their advertising arrangement causes less organic referrals. A shame, really. They have a great technology and I would love to root for them. But they need to straighten out the excessive advertising units first. Otherwise they're going to stay irrelevant to webmasters.
With the cheap price of bandwidth, might as well let them take your content, they might see the light down the road and decide to do the right thing.