I sent my wife a message from an iPhone 7 to her iPhone 6S. Both are running iOS 10.2 (14C92), but when she received my message, she got:
(sent with celebration)
(sent with love)
… instead of getting the cool effects I thought I was sending her. She can see the new emoji that come with the update, but not the new effects.
Best Answer
Not sure what happened, but eventually it just started working. Perhaps there's a glitch in the release.