thru your settings, you can set who sees your stuff (friends only, friends and their friends, whole network [ex - belize, Houston, etc], or everyone).
not sure anyone really uses the pages. i only look at them when i first friend someone. from there, its more a communications tool, with status, photo posting, PM, and IM functions. the news feed tells you all your friends' statuses. the more friends, the more feed. refresh it every so often.
so, for example, today an expat posted a funny pic, and many of us posted funny comments over the day, which we could all see. later, i posted a status, and elbert commented. then he cracked a joke & i responded. i also IM'd with a friend in tx, then one in belize, and left barb a message.
you couldnt find jan cuz he doesnt have a page of his own. if you had, it would say something like 'jan only shares some info. send jan a request to view his entire profile'. (paraphrase)
like any tool, it only works if you use it.