2009 was the first time and last time that I was spotting at london heathrow...747 was the king! Nowadays 777 and 787 are "kings"...of course you can see some A380....and another birds...
Ruanway In use was 09L. When this runway is in use normaly it didn't change...sometimes some airplanes land on runways 09R on peak time but the majority lands on the 09L. I only lost the Qatar A380 :-(
The spotting point is this one (search in google maps)...and you can access to it over the bridge or bellow the bridge, and you must be in de exterior road side of the rail road.