10221 UCS Super Star Destroyer - Executor

Confirm release in Sept 2011 - 10221 Super Star Destroyer
Darth Vader with the bounty hunters, Dengar, IG-88, Bossk & imperial officer

"This is my personal battle cruiser…and I did not name it the Executor for nothing!"
- Darth Vader

Length of Executor: 19,000 m, with a crew of 280k, 1,590 gunners.
The mother ship with complement of 144 TIE series starfighters, TIE starfighters, interceptor, bombers, Darth Vader's TIE advance, including AT-AT walkers, speeder bikes and other combat, support ships.

Check Aryo Gono's photo link

My estimate for 10221, probably 5,000 pieces, more than USD400.

Source from Brickset:
10221 UCS Super Star Destroyer

Aryo Gono's photostream - Lego Imperial Star Destroyer Fleet
Aryo Gono's Photostream

Star Wars Information on Executor
Star Wars Wikia Executor's