Phil Ringnalda is not amused over the advertising he finds at xml.com:

O'Reilly's XML.com, a site I used to take very seriously, because of all the scary-smart people who write there? Brought to you by hotel spam, mortgage refinancing spam, and one of those "directories" that only exists to feed off confused searchers by sending them right back around through Google's AdSense division when they arrive from a Google search.

How horribly low have we sunk, that I'm not willing to link to O'Reilly sites without a rel="nofollow", because they are a bunch of low-life search engine spammers? X-bloody-ML.com, something that I won't touch without a nofollow condom? This just sucks.

The ads in question are low key, text only ads - nn the other hand, they are spam crap that will show up in search results because of this, so maybe I should be as upset as Phil. In any event - if you are targeting developers (and O'Reilly most certainly is) - then this sort of advertising is pretty much guaranteed to generate negative linking.