Federer is still number 1 and will be for a few more years, however there are a few players that are starting to put pressure on him, Nadal is constantly improving and i believe will be the one to take the number 1 off Roger Federer, Djokovic i agree with dng-andre is young with plenty of potential but needs to learn how to finish matches, too many times he is taken to 5 sets and over a whole tournament, this takes its toll and is the reason he doesnt win as many tournaments as he could. Also dont forget Andy Murray, once fit he will start improving again and expect him to make big headlines next year.