This is the one thing that always seems to pop up that I must entirely disagree on.
"Twilight is aproaching Mary Sue Territory."
I not only think that it is incorrect but I am disappointed to see it thrown around as such. Mary Sue is NOT just how powerful the character is. Mary sue deals with many different aspects of the character.
If we were to use the currently accepted definition of Mary Sue, characters like Gandalf, Voldemort, Superman, Power Girl, and even Timmy Turner with his access to infinite wishes would all be Mary or Gary Sues. Strictly because of how powerful they are.
What makes it so they are NOT Mary Sues are how their weaknesses and characterizations are pulled off in each piece of media and entertainment they have shown up in.
Look at Twilight for example. Lesson Zero being the biggest one. She went batshit nutso over something as silly as being tardy. She is so OCD that almost everyone in the show visibly cringes whenever she goes off on one of her spurts.
She has very little confidence in herself as can be seen by not only how she acts about assignments, but also in Boast Busters when she refused Trixie's challenge.
Of course, these things are quite a bit less prevelant as it sits now, but that is because she is literally growing as a character. They all have since that very first episode.
Fluttershy saying NO to dragon migration, Applejack no longer afraid to ask for help, Rainbow Dash not being a complete tool anymore, etc etc.
As Tara Strong and several others have said, Twilight with wings is not what we are afraid it is. She is still the same pony with the same problems with the same friends. To walk away from the show now or to strongly dislike Twilight before we see season 4 can only be chalked up to how she looks. Not what kind of character she is.