I have noticed the following changes since the update to version 73920:

1. Introduction of "Hover Turkey" pet, as others have mentioned.

2. Fix of "Blackstar Shield" item. Was displaying two layers; i.e., two stars on shield for a time. Has now been fixed to display only one star, as was originally designed.

These are the only cosmetic changes I have noticed. It is always possible internal changes were made, but any such changes would be very difficult to ascertain.

At this point, I believe it is irresponsible to suggest changes to Mysterious Figure's loot table have been made. As we all know, loot is random. Randomness could easily explain the lack of purple/pink items in the short-term. And don't forget the changes that were made to Miner's luck in version 73918:
Quote Originally Posted by asommers:485574
  • Improved luck elixirs again. All loot that a mob will possibly drop is now considered when rerolling for loot.
Based on the patch notes for 73918, the guaranteed one rarity level upgrade appears to have been replaced with a true re-roll that considers the enemy's entire loot table. If that is correct, I believe that would explain the lack of purple/pink loot more than happenstance.