Seems IBM has got the go ahead for an even bigger and faster computer codenamed "Roadrunner", admittedly it intends incorporating PS3 chipsets into the design (I wonder if thats why the European delay) and if/when built will end up over at the Los Alamos National Laboratory in New Mexico.

They even have the coined termonology of "Petaflops" stated.

More info found through the link.
http://news.bbc.co.uk/1/hi/technology/5322704.stm