Remember; Memorial and Museum, two very different things. The Memorial, the waterfalls, are the things that are going to be done, or almost done by this time next year. There will still be a lot of work on the Pavilion, as you can see they are only now starting to put up steel for the structure.
Straight from the horse's mouth:
Full Report
here
Completion Dates
Transportation Hub 2Q 2014
Memorial
Interim Plaza Turnover (80% deck complete) 1Q 2011
Complete Plaza Turnover (100% deck complete) 4Q 2011
Museum Completion 2Q 2013
One World Trade Center, Freedom Tower 4Q 2013
Greenwich Street 4Q 2012
Vehicle Security Center 3Q 2012