Just as a point of information, my son applied for his first adult passport on December 20 and it arrived in under 4 weeks (yesterday). It was actually more like a 3 week turnaround since there were two federal holidays during that time.
He also got the passport card, mostly because it is another photo ID and I think we'll all get those to use as ID while ashore in wherever.
I opted to pay the extra and get the card in addition as well for the very reason to have it while ashore. Not like I'm going to be driving to Mexico or Canada. I remember asking about this as an additional ID and Dave said it was a good idea. Bravo!
If nothing else it would expedite problems should I ever miss the ship on foreign soil or something unfortunate would happen. Passport? Mine is locked in the cabin safe on that ship that is sailing away. Here is my card though if that helps.
The turn around time in Canada is 7 days or less. The last time we got ours it arrive in the mail in 5 days!!! Also the enhance driver license is no good for my wife as she does not drive, so we must still use a passport which we will always use no manner what. I drive, but I will still not use the enhance driver license as I have heard that some people have been question about these upon going across to the US by car.