The PlayStation 3 came out in 2006. That doesn't matter, people want to know about the PlayStation 4. Thing is, Sony's still focusing on the PS3. Oh, and the NGP.
From the get-go, Sony said that the PS3 will have a ten year lifecycle. That doesn't mean, Sony can't or won't release the inevitable PS4 during that time span. Heck, the PS3 is out, and the 11-year-old PlayStation 2 is still selling.