Hi, I'm the author of this story. Mozilla declined to make anyone available for an interview and would only provide canned responses to questions via email (included in the story).
I'm glad someone brought this up. (I'm the author of the FastCo piece.)
I wasn't sure if Samsung's claim of 1,000 apps included watchfaces, so I went through the Galaxy store and counted them by hand. The results (sections may be off by a few numbers as I was counting kind of quickly):
108 clocks
11 health
21 finance
211 lifestyle
17 social networking
129 entertainment
171 utilities
TOTAL = 668
Note that the actual number is lower, since several apps were repeated across multiple sections and I didn't subtract them from the total.
So, Samsung does include watch faces, but the ratio of apps:faces is much greater. As for the actual number not being 1,000 apps, I'm guessing Samsung is counting apps for different languages that wouldn't appear in the US store. I wasn't sure whether to get into this level of hair-splitting in the piece, but ultimately figured I could get into it more if someone brought it up.
Anyway, I wouldn't really discount the importance of watch faces, especially on Pebble since they're key to customizing the look of your device. And I think they'll get more useful with time; Jawbone's app is technically a watch face, for instance, and some faces can display the weather, battery and calendars.
I agree that bragging about app count stops being instructive at some point, but in this case I think they show Pebble has done a fine job of establishing itself.