I can't tell you how often i see a screen like this.

[polymath22]

i randomly clicked on link, and saw this page. notice how i already follow about every-other person? by my observation, it seems that about 1/2 the people will "follow you back" on any network.

I have seen screens like this more times than i can remember. they always get my attention, but i don't always get a screen shot. often i will look for "mistakes" in the pattern, such as 3 non-followers in a row. the center person "should" be my friend, so i will attempt to make it so., and usually they "follow back"

once you have reached the point where you follow half the people on a page, you have reached ubiquity on that network