seedcamp invests about $80k, which is nowhere near enough to fund a London-based startup with 3+ people for more than two years. although the official story may very well be that they "only started looking" in 2010 this does not match up with this simple fact very well.

Occam's Razor therefore suggests to me that it actually took forever to raise a round (despite nominally ideal conditions, such as a well-connected founder with a CS degree from Oxford, trip to SV, liked by startup media, simple to understand product, etc).