He uses the post office as an example of a government-run institution that hasn't cut off competition in the marketplace.
First, the costs at the post office are going through the roof and the cost of mailing a simple letter have risen dramatically over the past decade (33 cents January 1999 to 44 cents May 2009 - a 33% increase). Isn't this what CBO (Congressional Budget Office) advised Obama and Congress a couple of months ago? They conclucded that the proposed healthcare reform was not sustainable.
Second, FedEx and UPS are specialty services that deliver packages, not the everyday mail and junk mail we receive 6 times a week. Following Obama's analogy, this means that those who can afford the specialty health services will find a way to do so, and those who can't will be forced to use a government-run program that continues to become more costly with time while delivering poorer service using our tax dollars to subsidize its existence.
Back off the rush to approval of this monstrosity of a bill. Prioritize and attack the most important things first and authorize the states to implement plans best suited in each state. Learn from these smaller experiments and let each state modify their programs to include the best of the best from each individual state plan. Little steps along a well planned route are much more productive than a blind leap off a cliff in the general direction you wish to travel.