I use the Slashdot friend system as a method of highlighting comments by users, that for some reason or another, I would like to see more of. If you wish to reciprocate the friend designation, feel free to do so, but do not feel obligated except under your own criteria for assigning friend status.
Note that I feel this is largely pointless, as I doubt anyone really cares enough to actually bother looking at my user info, let alone a journal. If you are the exception, go ahead enjoy whatever information I choose to place in this location.
The first 90% of a project takes 90% of the time, the last 10% takes the other 90% of the time.