Just curious. If you aren't doing anything with a domain, would you use AdSense for domains or throw a few adds on there with some keywords? Let's assume there is some traffic coming to these domains already. Someone told me parking their domain got them a lot more money than when they had regular ads on it. Was this the case for anyone else?
I thought content ads will generate more but may be if the site is kind of dead, domain monetization is better. Why don't you try a test for few weeks and post your findings here for others benefits. I have parked domains with SEDO parkings and some dead sites that get a few visitors a day. May be I can switch those dead sites to Google AdSense for domains
The only thing is, I believe it is an AdSense Rule that a site cannot be just ads. There must be some body of content. However, one must only add a few paragraphs of legitimate content , which isn't very hard. My sites have a 15pixel link banner at the top, followed by search, followed by two side by side Large Rectangles, one image, one link. After that is about 200 words relevant, original content. Not junk, but definitely quick and common knowledge to most people. I plan on doing some experiments to see what works best, and then i'll share the results. We'll see.
I have not tried adsense for domains yet but developing a content site will get you better returns in my opinion.