We have no idea if online ads actually work at the scale of huge corporate brands competing for mindshare. I'm pretty sure it works for smaller outfits - every time I find an appropriate place to run an ad campaign, I see a permanant uptick in readers of my web comic. Eventually I'll have gotten everyone in that place who's going to be interested in my stuff, and I move on.
Actually, per the article... its actually harder to know with certainty that ads are working for smaller outfits. Large campaigns are the one case where you might accumulate enough data to know.
Willing to share where you advertise and why? I've got lots of friends and relatives doing comics online, would love to have a little specialist knowledge to help them out.
Mostly just Project Wonderful, an ad network that mostly sells ads on web comics. It's pretty easy to drop a couple hundred into a broad campaign, dink around in your analytics to see what sources give you engaged traffic, and drop some more money onto those specific places.
Also your friends and relatives may want to check out webcomics.com; I don't agree with everything Brad says about Making Comics On The Web but for the most part his site is full of a ton of great advice that's well worth the yearly fee.
