He got a good crack when Haddin was first made Australia's main keeper, and got 500 odd F-C runs @31 and had 33 dismals or something, but since then Peter Neville has taken over and is a better keeper and better batsmen, although Smith is a larger lad and can hit a ball. He hasn't played any F-C cricket this year as Neville has kept in both of NSW Sheffield Shield games so far, and tbh I don't see him getting a go any time soon for the Shield team.
Smith was only playing today because NSW have players with the Aus team in SA and they also have a fair few injuries, so he was lucky to get a game in a away, but he took his oportunity and made it count.
The innings was at North Sydney oval which is one of the smallest fields I have seen top level cricket being played. I'm pretty sure that all the fields I play on are bigger than it. Here is a video of Khawaja getting a 121 on it last season -