More info about Legendary Edition please.
It's all on the website for the game.
The current game uses Living Rule Book 5 (LRB5), the Legendary Edition will use the rules currently used in competitions which are now set in stone and unlikely to change for years.
There is also around 20 races compared to the 9 with the Dark Elves you get in the current game. All of them except Chaos Dwarfs (don't ask) and the 3 non official races.
The LE is trying harder to be strict to the rule set, using board game Wizards, weather and all sorts the original game cut corners on. The only thing we will be short on will be some of the Star Players I believe but there will be a lot more Star Players in there.
There are other features and updates that are yet to be revealed.
There are some fantastic leagues running at the moment who I can only imagine will all be going LE so it would be a great time to join. Although it might be an idea to start learning the game because it takes crazy amounts of games to master.
http://www.orca-cola.com/forum/