What we heard: There's not much at the heart of the Bitmob article. The report cites a source with the quote, "PlayStation 4 in 18 months." The source apparently heard the news during "a 'high-level meeting' at Sony."
The next paragraph in the article says it's not clear if what happens in 18 months is supposed to be a launch or an announcement. The one after that emphasizes that the source in question isn't a fake or a show-off, and then the rest of the story is reserved for the writer's analysis of what Sony should put into the PS4 and when it should launch, concluding with a restatement of the 18-month window and a "We'll see."
The official word: "We don't comment on speculation or rumors."--A Sony representative.
Bogus or not bogus?: The PlayStation 4 is coming eventually. That's not bogus. But at this point, so far from the thing's actual launch, any details--even ones that come directly from Sony--are unreliable at best.