Since so many of you are likely in the middle of Pokemon X and Pokemon Y right now, I thought I’d relay this big warning involving both games. I personally didn’t experience this glitch, but there are multiple reports of it happening. According to Game Informer it has come from multiple different regions, so it isn’t specific to one region’s version of the game.
The game breaking glitch revolves around saving in the biggest town in the game, Lumiose City. What makes it worse is that you actually will visit this area twice in the game for a decent amount of time, so the odds of you saving there are pretty high. The problem is that the game locks up when trying to save. Upon restart, the save file will load in the same place and lock up again, causing an endless loop that requires you to start the entire game over again.
Be very careful as this could potentially really mess up your game. We don’t know how widespread it is yet, but be forewarned.