If you're still wondering (I guess not, LOL),
they're either a deliberate scam, or they're just dead like the rest (someone else on this forum said: "last time they've updated their site was in 2001!", and another: "The earnings page shows statistics from May 2001. The last news release is from 1999.", and yet others were still waiting for the surfbar download, or for their paycheck after years)
There are few survivors, and even those have low rates now.
I guess the paid-to-surf companies themselves lost their earnings from advertisers as well when rates went down 100-fold, so they lost their interest in it.
evolution continues, auto-surf is the new thing (allowing advertisers whole screens instead of small banners), but I don't like it...