Read to the end for a surprise (and partial spoilers) 
So in spite of my PBS billing the special as Postcards from Ireland (without promoting it as the holiday edition), I tuned in anyways, without much hope of seeing the Christmas videos. I was mostly watching for the interviews, since my PBS station didn't show the interviews during the original run of Postcards.
I actually started 20 minutes late because I thought my DVR was recording it, but turns out my cable provider's guide had the Postcards special starting an hour later than it actually started. I just tuned in case somebody messed up and sure enough, someone did.
It's been a while since I watched Postcards but something seemed a little off to me, like they were changing the order or skipping songs. The interviews were talking about songs in the next segment that were never shown and about songs in the previous segments that didn't appear. I figured at first that PBS was just running the interviews out of order. They did some more interviews during the pledge break after Wild Mountain Thyme, then ...
... The Christmas videos played!

There was one video for each of the 4 tracks on the Christmas Cards from Ireland EP. In the order they appeared in the Holiday Edition Postcards special:
- O Holy Night
- I Saw Three Ships
- Silent Night
- The Toys' Waltz
I wasn't a big fan of the EP. None of the tracks worked very well for me. But just like Postcards, somehow seeing the emotion the girls were pouring into the songs made a huge difference. All the problems with the arrangements and mixing got supplanted by the visual treat unveiled on the screen.
The first three songs were filmed very much like Postcards was. The dancing during I Saw Three Ships was borderline over the top, but I appreciated the enthusiasm. The highlight was definitely The Toys' Waltz though. It wasn't how I'd imagined the track unfolding
The Toys' Waltz was really cool! It wasn't how I imagined they'd approach a video for this. I imagined it in my head as toys dancing around an empty room during the night. But the way they ended up doing it worked REALLY well! I think aside from maybe The Parting Glass (which followed the Christmas tracks to close out the special), The Toys' Waltz was my favorite of all the Postcards / Christmas cards videos. I want to be those kids! Forget Santa, Celtic Woman's coming down the chimney this year! Why can't Celtic Woman come to my house to have a dance party and lead me on an adventure through the woods on Christmas eve? Lol. I won't spoil the rest of the cool things that happen in The Toys' Waltz yet in case some of your PBS stations actually end up showing it, but oh WOW I loved it! The magic of Christmas and the magic of Celtic Woman found life in this song! Wooooo!!!!
UPDATE:
As of the time of posting, the "Celtic Woman: Postcards from Ireland (Holiday Edition)" version listed on PBS Passport is actually the regular version of Postcards (they accidentally posted the regular version instead of the Holiday version I guess).