As a general rule, I would agree about the agenda, except perhaps the agenda to hang out in chat rooms talking about keyboards (and sometimes to e-stalk Ripster). My point is that there's something in common. And any time you have something in common with several individuals, you can group/classify those individuals by that which they have in common, and all of a sudden you have a group.
First of all, despite my dislike for circular discussions of the scope and denotative limits of specific words (linguistics student here) I'm going to have to point out that having something in common, i.e. an interest in keyboards, is not equivalent to having an agenda, e.g. a desire to denigrate Ripster or a desire to edify dracaXL (please do this). Conflating the two by implying talking about keyboards is equivalent to a dislike of Ripster is, as I said before disingenuous. Correlation is not causation.
To disagree with this point is to say you are fine with the assumption that you (as part of the IRC crowd) are part of keyboardscience.org and #keyboardscience as much as #geekhack, and this site is a troll orchestrated in part by yourself? Of course not. That was the original point, not the specific definition of 'group'. The implication of HaveANiceDay's (no offence to you at all, Sir, I'm sure it was unintentional) post was that all of #geekhack created a new forum solely for the purpose of trolling (which is of course not the case).