So now I've successfully upgraded to 1.23, but discovered that the Monobook skin has been radically changed in its design. Previously it was easy to insert ads into the skin, but now I'm at a loss for how to do so.
The specific places I'd like ads are a banner (728 x 90) at the top, a skyscraper in the sidebar (160x600), and a banner at the bottom (728x90).
I've looked around and there don't seem to be any good solutions that allow that level of control, so I have to assume I'm supposed to just go ahead and figure out how to place it in the skin... but yeah, it's not easy. For example, there's an array that creates the navigation sidebar, and I'm uncertain how I'd introduce an additional element that would contain an ad unit (and other stuff -- in the past we also had some selected links from included php files).