Who Can Buy or Sell Text Links? Google Decides.

Trying to understand Google's postion on Buying Text Links can be tricky.

Do they just devalue the links? That seems likely. Do they penalize sites for having these links? Some believe so. Do text links work despite Matt's warnings? Sometimes.

But how does Google feel about the link sellers? Surprisingly Fine.

Until today, it seems. AdvertiseU, a notorious link seller, has been banned from Google. While most everyone went up on the latest PR update (i got some PR7s), AdevrtiseU dropped out. Try a site: search in Google and you'll see. AdvertiseU sells text links on many major pages, which I will not disclose here. You probably recognize this logo

from many of their pages.

Were they banned for selling text links? If so, it will be the first time any search engine has specifically penalized a site or broker for selling text links. Did they violate some other SPAM policy?

If it was for selling links, then why them? Many other sites openly sell text links and seem to flourish in Google.
Blogs do it: Zawodny's Blog is a PR8 and SERoundtable is a PR7. Even non-SEO blogs - Gawker is a PR8.
Marketing Firms: VKI Studios and SubmitExpress have a PR7.
And Link Brokers: Text-Link-Ads, LinkWorth, TextLinkBrokers and LinkAdage are PR6.

What made AdvertiseU less seemly than these sites? They sold links for PR as do all text link brokers. Was it they openly listed themselves (through an email address) on the sites where the sold link appeared? Is this just the beginning of the end for text link brokers?