...and the thread turns negative.
As it turns out some of us were born with fixed gear knowledge imparted from the gods upon our conception. It is our sworn duty to look down on people who have to learn by actually building/riding a fixed gear bike to understand the mechanics of it.
The bike is basically fine. Make sure your cog and lockring are tight (your LBS can help you with this if you don't have the tools yet), tighten up the chain a bit, and certainly put the front brake on when it arrives but otherwise- ride the hell out of that thing and have fun!