My understanding is that they found the HP ProCurve switches were a better deal to buy two chassis and stuff all the blades into one box rather than buy the blades and add them to one. It was cheaper that way.
The Computer History Museum is really cool! I highly recommend geeks check it out if you are in the area .. especially if you can catch some of the demonstrations/tours.
Looks like most of the midsized companies "data centers" I've been in recently. At least the cables aren't all over the floor for you to trip on as well.