What's to say he wont be making more games? I'm holding my judgement until I give it a try- it might still be fun.
Saying that... this kind of happened to Yuji Naka after he left SEGA. His new company, PROPE, have made a couple of console games (that have both been quite shallow on content, imo) but spend most their time developing ios applications. I'm not against that but... they're just, for the most part, not very good.