Mark's place is awesome.
Quite neighborhood. Spacious and luxurious apartment.
Great hi-speed internet, and even an AppleTV if you are an Apple fan and want to watch on the big LCD.
Very well equipped kitchen. Even a washing machine / dryer if you need to.
Perfect location, 5 min Westfield Mall. Great for shopping, restaurants, etc.
If you want to reach ExCel - use the DLR from Stratford International, 3 min walk. To reach Central London - use the underground from Stratford station (7 min walk).
One of the best places I stayed in London so far. Will definitely book it again (if it is available) on my next trip to London.