A pre-order listing recently popped up on Amazon for 'My Little Pony Friendship is Magic: A Very Minty Christmas' with Friendship is Magic voice actors and staff credited in the product details. For those who are not familiar with older generations, A Very Minty Christmas is a G3 film from 2005 starring everyone's favorite sock-loving Christmas pony, Minty. Are we going to receive a G4 reboot of the movie?
It seems a little odd, given that the Friendship is Magic universe has already dubbed "Hearth's Warming Eve" (S2E11) their staple winter holiday, not Christmas. The run time for the two films also matches up exactly (66 minutes). It's highly likely that the movie is being reissued and Amazon messed up the credits. The DVD, although G3-based, may be bundled with the G4-style Minty brushables that have recently been showing up all over eBay and Taobao (more info here).
Still, we won't know for certain until more information is released. You can preorder the DVD here for $9.99, set for release on October 8, 2013.