Visiting Friends

Interesting idea, but I doubt I would use this much to reward specific friends who visit me often. Really all I want from a friend is for him/her to be active enough that there are always available buildings to tap when I visit. This means I can just go straight through my friends list in order and get the maximum possible reward, and don't need to worry about finding specific names in the list who are active or who visited me. If my friend also visits me, that's great but not something I am willing to take the time to keep track of.