1) Twinkle: upload a new photo of something that sparkles (like a Christmas tree or a chandelier), and we'll gift you a version with lights that actually twinkle.
2) Snow: upload a new photo with snow to Google+, and we'll gift you a version with snow that’s actually falling.
Here are 2 examples:
Please note that this only works for new photos. Check the animations generated for other Google+ users: #AutoAwesomeTwinkle and #AutoAwesomeSnowGlobe.