MaximumPC has build one of the first Intel Nehalem systems, you can check out their photo coverage over here.
This particular sample was the 2.93GHz Bloomfield, which will put it in the mid-range of the three desktop Bloomfield chips expected to be due by the end of this year. One thing we immediately noticed when holding a Bloomfield next to a Core 2 Quad is how much larger the actual chip is. The new LGA1366 socket is also a bit larger, of course. As such, previous LGA775 heatsinks will not be compatible with the new CPU. Some coolers may possibly be adapted to work with Bloomfield with new mounting brackets but most will need new heat sinks.