I dont have a proxy site, but most of the traffic for a few of my high-earnings pages come from the same kids in school that use proxies (most of them looking for proxies).. Things have been slow for the last week or so, but it's picking back up yesterday and today..
I also run a proxy and I think the visitors will be less in vacation time.. because kids will be out of school and can get to myspace and facebook and bebo from their own pc's