As reported and verified on TheSilphRoad reddit, a Trainer caught a Rattata and his Rattata turned into Ditto after the capture screen! More than hundred other trainers reported the same phenomena: low CP Pokémon turning into Ditto after being captured!
The tracker seems to be active in more places worldwide and the game is running in 60 FPS for an increasing number of players. Current list of locations where tracker is available:
Australia US West Coast US Midwest Mexico Not yet:
New Zealand US East Coast Europe S.E. Asia Japan This is what reddit says about the recent happenings: