Microsoft made a splash this week by adding new perks to its "hey we'll pay you to use our search" program and may actually be making some progress--sort of--with it. Hitwise has some interesting research on the topic. In a blog post Hitwise director of research Heather Dougherty notes the following: Traffic on MSN Cashback and SearchPerks is up; Actual searches on MSN's properties are flattish; ...