The first games in Japan will be the scrolling fighter Fist of the North Star (released in the West as the heavily censored Black Belt) and the cute shooter Fantasy Zone.
Our contact inside SEGA Europe has confirmed that the Western VC will get Master System games in the next few months, possibly even as early as March/April time. Each title will cost 500 Wii points to download. Western releases have yet to be confirmed, but seeing as we got both of the aforementioned Japanese games it's highly likely that they'll come out over here too.
The Master System should be interesting for most US gamers as the machine was largely ignored when it was launched there, and Sega only really found success in American when the Genesis hit the market. However, in Europe the story was different as the Master System easily beat the Nintendo NES thanks to better marketing and a wide selection of decent software.