When the caps are dropped, it's really not going to be that big of a deal when you compare it relative to everyone else since most sites are at the cap. Also, the weighting scale is *not* going to be a linear scale, it will be logarithmic instead.
The more pages you run ads on within a single domain, the less weight each individual page will give.
Basically, It means you get more weight for the first 100 pages then for the last 100. How many pages are in between determines by how much. That way those with insanely huge sites benefit more but don't dominate. [added] - Shawn provided a perfectly good answer while I was typing[/added]