Honestly I wouldn't be surprised if this were a controlled leak, Sony wants something to keep people excited about the PS4 until E3. A few images is a perfect way to build up anticipation for the full trailer at E3. While it would have been great to have it be a surprise at their press conference, would anyone really be too surprised that it came about? At this point, it is defintely going to serve its purpose of getting people talking about the PS4 for the next month.
Demonite probably did what he wanted teasing this title, coming back in would be giving more information than he (and Sony) want. Not saying he is a plant or anything, I just think that he is happy giving tidbits of info to Gaf, now that the cats out of the bag he has nothing else to say until E3.