According to the post, though the actual updates and change logs are missing, 16 Google apps have updated since Monday. I was able to download a Google Earth update on my Nexus 4 earlier today, but Gmail, Drive, Calendar, Wallet, and Keep remain unchanged.
So, what's going on here? Well, one logical conclusion could be that the unreleased updates are pending the announcement of the Nexus 5 and Android 4.4 KitKat. We still don't have any word from Google as to when those announcements might come, but the latest rumors point to Thursday or Friday.
Indeed, it makes sense for Google to update all of its core apps once a new operating system is made available, even though the Nexus 5 (presumably) won't be in consumers' hands the same day. It's not uncommon, after all, for users to see a rush of app updates just before a new Android version becomes available (that's also true for iOS).
Also, as we've seen in the past, Google has done a terrific job of making the latest release of Android available to older Nexus devices on the same day it was announced. Sure, this could always be a glitch in the Play store, but that theory isn't as much fun as updates waiting to be released after an announcement.
Hopefully, it shouldn't be too much longer before we learn more details surrounding these mystery updates. And in the meantime, if you're able to grab one of the updates listed on the Reddit page, feel free to post about it in the comments.