They already did nerf her auto range and it made a big impact on bottom lane. Right now annie really is weak vs poke because she has no gap closers etc. Her long poke auto gave her an way of being very strong in level 1-2 against pokey mages in the past but then around level 3 she would start to lose trades until level 6 allowed a flash tibbers for a kill, so the objectives between level 3 and level 6 was to hit level 6 first and to have your opponent at around 70% health. Her late game is strong, but only if the team groups to fight. If you waste your flash-tibbers on a uesless pick it can be pretty damaging to your game and if your teammates won't go for objectives you don't have much say in it because you don't kill towers very well.
The real issue with annie is that she's so easy to learn: you can be pretty good with her after a single game and very good after a few games... and then it's really hard to go back to one of the other champs that are harder to learn. Annie's a great way to get new players into the game right now, sort of, for that reason. :)