What do you think? Traffic is good anyway but bookmark visitor will not click on PPC ads. And even more, he become blind for any ads. Is returning visitors so important for revenue? I think fresh traffic is more profitable.
Greg, are you sure? You think if everyday visitor sees ad he will funally buy it? Returning visitors can become a members, so with huge amount of them webmaster can build a good community.
Depends on your site. An online shop would be glad with return visitors as an information site depanding on adsense etc would like fresh visitors. If you are selling something yourself or by affiliation and people like your site and are returning you build trust and they will more likely buy from you.