Ben Heck has peered into the realm that is the 60GB Xbox 360 in an attempt to see what changes have been made. What he found was ... the same as we've seen in recent hardware iterations -- including the newly developed 65nm chip. The only major difference Heck was able to spot is the size of the harddrive, go figure on the 60GB model, and the placement of some chips within the system.
While the current models look quite different in comparison to launch units (inside that is), the extra heatsink among other things means the 60GB model essentially the same as the units currently on the shelf. As long as they aren't on par with the RROD'ed units filling up crater sized holes in the Mojave Desert we'll be happy.