Sure, Wikipedia may not be “advertising” in the strictest sense of the term, but to me: a banner ad is a banner ad is a banner ad. Here’s what those banner ads look like on Wikipedia (the puzzle piece at top with a red button next to it for donations):
It appears (sample of 2-3 random articles) that these banner ads are now atop most of the entries in wikipedia.
On one hand I think it was rather noble of Wikipedia to refrain from commercial advertising on its site (because as Lawrence Lessig mentioned at a recent event of ours: commercial income might cause us to question motivations of contributors).
Yet on the other hand, I find it ironic that wikipedia’s “supported by donations” model has lead to banner ads on every page anyway. I’m guessing I’ll be flamed for saying it – but I say why not go the whole way. If we have banner ads on the top of every page, I suggest opening them to the highest bidder.
Done right, perhaps there is a way ads could actually keep wikipedia pure. Instead of hundreds of companies trying to quietly and subtly weave their agendas into wikipedia entries on the sly – why not give this commercial activity a proper and transparent place on each page and call it what it is – marketing!