Well, YEAH. Lots of people. But you visited last on Sept 5 and then sporadically in August. You have likely been dumped from many people's friend lists.
You currently have 48 friends... I'd wonder how many of them are currently active, and how many signed up at the conference you attended some time last August.
And having only 48 friends is a bit like having a conversation with yourself in a closet. If you are serious about developing a network here, prune the deadwood and reach out to active Plurkers here who have
similar interests or job descriptions to yours. If you put a few minutes into this a day for a couple of weeks, I think you'd be surprised at the value.