Portal 2- co-op detailed

In an interview with Funabulism, Valve’s Erik Wolpaw and Chet Faliszek, chief writers of Portal 2, dropped some details about the co-op mode of Portal 2, telling us that the co-op mode’s story takes place after the single player story (even though you can play it before the single player) and maybe even dropped a hint about Portal 3.

Wolpaw told the site that the co-op story does tie into the main story. “The co-op story happens after the singleplayer story,” he said. “Having said that, you don’t need to necessarily need to play them in that order.”

“But you know that apeture science isn’t going to get blown off the face of the earth by the end of Portal 2,” he added.

Does that mean that we have not yet seen the last of Portal. Will Valve be back with a Portal 3?