We think it's bad here, it's 1 degree (-17 celcius). I have friends in Ontario where it is currently -50 celcius (-58 faranheit) plus wind chill. They have had just over 40 inches of snow in the last week. I love winter.
That's wise. Get the electric an plumbing looked at, too. Once the drywall is on it is mighty tough to fix those problems. I wouldn't bother with a drywall inspection, frankly. You can look yourself and see if it's crap.
If this is a big-name or even well established builder the inspectors often skip steps. They'll wait until final inspections to make sure the house is standing and it's not going to burn down with loose electrical sockets or whatever. It's actually quite pathetic. Some areas are much stricter...