MBK's forthcoming book The Meillassoux Effect (2014) has some arguments that are nicely laid out by Terry Blake of Agent Swarm blog (links below).
http://terenceblake.wordpress.com/2014/02/17/mehdi-belhaj-kacem-on-meillassoux-3-demonstration-vs-description-in-the-genesis-of-stability/
http://terenceblake.wordpress.com/2014/02/17/mehdi-belhaj-kacem-on-meillassoux-2-meillassouxs-bluff-and-the-phantom-problem