Uncharted 2 will be a lot more frontloaded than the first Uncharted but still there is a lot of competition ( MW2 and AC 2 for example) so I'm thinking 1.7-1.8 million tops before the end of the year...
Probably 2.5 millions lifetime ( I'm afraid the huge number of quality releases in Q1 2010 is going to cut the legs of many of the holydays titles).