During the presentation, the rep from Massive, JJ Richards, talked about the three types of advertising that they're running: in-game, around game, and for game. In-game is what you usually see in EA's big sports titles: big billboards that sport real-life brands, or even in-game items like cell phones and clothing that advertise real objects. World of Warcraft obviously isn't much of a candidate for that type of advertising, but Massive does cite them as a huge success for the second type, "around game": they take full credit for the ads over on the forums, as well as the ads we'll eventually see in the Starcraft and Diablo Battle.net interfaces. Strange that they didn't mention the gold ad slipup (/sarcasm). He also suggests putting ads in the WoW launcher, but at least agrees that those will have to be extremely game-related if they're going to get away with it.
And the third type of advertising Massive does is "for game," where they use the various Microsoft properties like Xbox Live and Hotmail to do targeted advertising at gamers -- using Netflix queues on Xbox to shape Hotmail ads, and so on. If that all sounds sneaky, so be it (don't forget that this presentation was made to a bunch of marketers, not necessarily actual gamers). But it sounds like Blizzard has made a nice big deal with Massive (despite the fact that we're still paying a tidy subscription fee every month), so whether we like it or not, we're going to be seeing exactly what they're planning in our games in the future.