Applications need to be 'retina aware' to actually get the full resolution, otherwise they are told the resolution is 1440x900 (this doesn't include fonts, and

Applications need to be 'retina aware' to actually get the full resolution, otherwise they are told the resolution is 1440x900 (this doesn't include fonts, and other system-rendered features, which the OS can always render at full resolution). The program icons also need to be shipped in a higher resolution.