It makes Tim Cook's (aka Suply Chain guru extraordinaire) comments on his regret over the iMac shipping debacle a little hollow.
There are a lot of things in play here - a new US factory, maybe too small of a factory, an overly elaborate production process (crazy case, innards, heat sinks, etc, custom motherboard, video cards, etc), a pent up and maybe higher demand than was expected (ie the next model won't suffer from this pent up demand, I know I have been on the fence for several years).
The computer is stunning though.
Only real problem is... computer tech moves pretty fast. You don't mind waiting on a Ferrari, but you do mind waiting on computer tech. The nMP was announced at the start of the Ivy Bridge era and with 7950 era video and will ship maybe too close to the Haswell and next gen video card era. This is a problem because I bet nMP v2 will start with a Haswell 6c as its base. Tech moves fast, yes, but you can't ship a gen behind, that does not sit well.
I am hesitant to call them clowns, but a strong case could be made that they clowned it.