the transport system in (central) London, if not the cheapest, is quite good. you can easily travel between different parts of town without much hassle. I've been to Notting Hill, the area around Liverpool Street Stn, up Brick Lane and into Hackney, then down to Millennium Bridge and City of London and then up to Soho within a day (on my own though, not with a big group of geezers). Also, I liked taking photos in the subways (the light is better than in Berlin's U- and S-Bahn.)
Of course you can't cover all of London within 2-3 days, but those who were in Berlin faced the same 'problem', still had fun and didn't stay in one single part of town either (although you folks still missed a lot if I might say so 😀 )
I will probably stay in Oxford, most certainly if my girlfriend comes along, so I'm bound to deal with some travel time. But I did enjoy the 'early' train rides to Paddington Station the last time.
Kully, what about dropping Robert (De La Luz) a line about the meet?