Apple has confirmed to eWeek, that some Mac Mini models may have higher specs than published on the box. However, Apple isn't hurrying to re-label the boxes, no quite the contrary, Apple is going to continue selling a mix of slower and faster machines until the entire stock of older machines is sold. The new machines are apparently shipping with a slightly faster processor, updated Bluetooth, more video memory, and a faster "Superdrive".
Users have no way of knowing if they are getting the machine on the box or something better. While it's certainly a nice surprise to a user, to get a faster machine, it will certainly make new owners of the slightly older model a bit angry.