I have tried this before with good results. Anytime you take the time to try and make the site look REAL with a logo and have an attractive page with a few related graphics, the user seems to click alot more because they actually think the site contains what they want. My problem however is that I don't have the google direct connection (have to go through sedo/etc) so I had to try it with searchfeed.com etc whos payouts are too low to even make it worthwhile.
If you are a direct partner of google (congrats on having that much traffic
) I would figure this would be hugely beneficial, especially since you can control the meta content for the search engine spidering. This works especially well for domains that are expired withalot of old visitors etc. I tried this with old adult expired names and the type in visitors would just think that the site had been redisgned, my clickthroughs pretty much doubled because of this.