Huh. Mapnificent is exactly what I've been looking for recently after a change-up in local transit routes. It would certainly make it easier to eyeball "short trips" when considering the intersection of multiple transit modes, assuming it's accurate enough.
It's a nice idea, but London is hopeless - looks like they've missed out the rail network completely. I guess other cities may be better, but you really only need to miss out one key route or mode and you change the map completely
* BART map, one minute per hexagon - http://transitmaps.tumblr.com/post/133579339455/lopato-bart-...
* Mapnificent, covering dozens of cities - http://www.mapnificent.net/
* OneBayArea, including housing prices - http://maps.planbayarea.org/travel_housing/