The guys at Macminicolo.net have already gotten their hands on a new Mac mini, and they offer not only the obligatory unboxing, but a dis-assembly as well. As before it seems you can take the mini apart with a putty knife. A few parts have been moved around or re-oriented, and there are now three antennas as well as a SATA optical drive (i.e. SuperDrive).
Now that they've got a look at the guts they promise to start benchmarking the new minis in server performance. Needless to say, they're optimistic that the new machines will make even better servers than the last model.