n90bar:
Were u on a A340 by any chance?
It was a B744.
Gonzo:
Thanks for that - the PA announcement as we approached the London area made mention of 15-20 minute delays, so I assume that's what was happening. For some reason the in-flight entertainment was on all the way from pushback to arrival at the gate, so I got to see that we only did one lap waiting for a landing slot (normally the IFE is off by then so we don't get the enlightenment)