Today was AppleJack's 100th appearance on My Little Pony Friendship is Magic. I tallied appearances of characters and she is the first of the Mane 6 to hit 100 physical appearances. She was immediately shown to be a family pony and caring to everyone. When your in trouble, you were always sure she would give you an honest answer.
This apple farmer has a down to earth wisdom that still has more to come.
This only includes appearances that she, herself, appears outside of a mention or a photograph or a statue for some ponies.
Keep in mind that I did not include the leaked episode Scare Master as it did not officially air yet.
As for the other main characters, here are the their current tallies as of today.
Twilight Sparkle - 98
Rainbow Dash - 94
Rarity - 94
Pinkie Pie - 94
Fluttershy - 88
Spike - 85
They are all close to that point as you can see. Tell what you all think in the comments