One of the "benefits" of earning 200 rep points is that fewer ads are displayed to you. Instead of seeing three zones (Leaderboard Top, Leaderboard Bottom, and Sidebar), you see only one (Sidebar).
Now I put "benefits" in quotes because I personally don't consider less advertising (especially on SO) to be beneficial. Of course, as the "ad guy", I really don't care because the loss of impressions are statistically negligible, but as a member I feel that I'm missing out on something.
We work hand-in-hand with each sponsor to make sure their ads are high quality and relevant, and we won't even talk to companies with a product/service that we know is a poor fit. And now that there's no more AdSense, that's the only thing we see.
There are so many awesome products/services that I've found through relevant ads, most of which solved problems I didn't even realize I had (or were solvable). Cushy CMS, for example, has very recently "changed my life". And of course, there's no other way I'd find out about these, because I don't spend a whole lot of time reading reviews, etc.
So long story short... I think the "reduced advertising" thing should be changed to work as follows:
On the User Profile page, there would be a Checkbox that reads "Show Reduced Advertising". The Checkbox remains hidden until the member reaches 200 rep. Upon reaching 200, the box gets automatically checked.
Basically, it would work exactly the way it did before, except you get the option to turn off reduced advertising.
And yes, of course I'm biased. But still, Good ads are are a Good Thing.