My boy is also a "small b", born in Dec 2010. I would let him study playgroup/N, and be a "Big B" in K1. It's because I was a "small B" when I was a kid and i think it really matters!
My son is 2010 Dec small b, my ideal plan is let him to apply some N1 class. If he will get any one N1 offer, let him to study K1 in this KG, and let him to be the next yr extra large b and apply another better KG (But, actually I think it's very difficult for him to get any N1 offer in this year!!)