When The Boss is speaking like that, the possibility of that being the truth is highest possible in my opinion. If you read it well he's actually grinning about it. Despite that this is not an official announcement in any way. Some are aware that Duke Nukem Forever is coming, however as far as I know it it has never been officially announced.

I wonder how EA being a partner in this project will effect the game. I'm more than sure that BioWare got the deal to make the game long before EA bought BioWare.