We reported earlier about the A Wedding in Canterlot board book that is up for preorder on Amazon, but apparently there is more to the story! The above description landed in our inbox not too long ago which mentions the title of the season finale two parter as "A Canterlot Wedding".
So there we have it, the title for the last two episodes of the season! I can't believe how fast time has gone, but we still have several weeks ahead of us to enjoy.
You can find the source of the description at the Simon & Schuster Digital Catalog.
Thanks to Jesse for the information!