25 fps are already enough for smooth animations (e.g. pal tvs have 25 fps [but interlaced]). the new cs2d will have a fps limit of 50 too. its already programmed that way and there is no reason to change it. no normal human beeing would be able to see differences between a cs2d with 50 and 100 fps. thats for sure. this way cs2d also doesn't need so much cpu power and you can run more other stuff in the background.
please don't just cry for more fps if you don't really have a clue. it is NOT as easy as more fps = better, faster game.