In the days leading up to this, some journalists had commented on the good interchanges between Roberts and Obama, given that Obama had opposed the Roberts nomination.
Now, suddenly, Roberts, who is reputed to be an expert on the Constitution, changed the word order of the oath. This is how the oath is specified in Aricle II Section 1 of our Constiution:
I do solemnly swear (or affirm) that I will faithfully execute the office of President of the United States, and will to the best of my ability, preserve, protect, and defend the Constitution of the United States.
In Roberts' version, the "faithfully" went wandering. There was a pause as Obama, clearly recognizing that something was amiss, didn't respond. Roberts then reprompted, still incorrectly. Obama did his best to repeat -- and the somewhat unconstitutional deed was done.
I suppose this was just a case of nerves on Roberts' part, but I can't help reading it as an omen.
Let's hope that President Obama will find nominees for the Supreme Court who will prove more careful readers of the Constitution of the United states of America.