The domed building in the center is the 2 World Trade Center Building. It was severely damaged by falling debris when the World Trade Center towers collapsed. The building on the right is the new One World Trade Center Building.
Here is a link to a very moving and interesting PBS/Nova video about the attack, the Memorial and the building of One World Trade Center. Walter Koenig brought it to my attention, Click Here: http://www.pbs.org/wgbh/nova/tech/ground-supertower.html