I have this mug, and while the colours are a bit off for some ponies (particularly Firefly's pink, and some of the other ponies' pink hair), the ponies on it are as follows:
Snuzzle
Glory
Firefly
Starshine
Gusty
June Birthflower Rose
Lickety-Split
Minty
Princess Sparkle
Powder
Sundance
It's a cute mug, though.