Nowadays whenever I'm active on Digg I usually get notified that I have a new fan. Generally the fan has recently added many friends and they have very many friends. Three recent examples are Damian86, Madrid Design and muzicman. The sheer number of friends and the speed with which I get added after I do something on Digg make me think that bots are at work, perhaps using real-time data from Digg Labs.
I want to be cautious about accusing users of being bots but the same sort of thing keeps happening and I'm becoming more and more convinced that I am dealing with bots. Earlier I contacted abuse at digg dot com and I just disabled e-mail notifications for these events. I hope something will be done about this issue.