I have to give an alternative view from Stevey on his perception that there are cliques... yes, some people do stand in groups but you'd expect that in an environment where people get to know each other.
If people fancy meeting up with some other London AB/DLs, a few of us meet up for some friendly drinks and chat before heading on to the ABC club, third saturday of each month.
Along with a few friends, we had a pre-ABC London afternoon drinks social in August - it went pretty well with 18 of us there at the peak! So we're having another one this month with a view to making it a regular monthly get-together.