You can transfer your characters from Cataclysm x175 and MoP x10 realms to MoP x100 realm.
You can do it by using "Transfer" NPC which can be found in Orgrimmar and Stormwind (including faction hubs in Vale of Eternal Blossoms for MoP x10 realm). In a month the realms will be closed and you will be able to transfer your character only from your site's personal account.
- Before transferring your characters check how many of them do you have on x100 realm (you can have 10 characters at most on one account)
- Be very attentive while using transfer function, because it's irreversible.
- Take everything you need from the guild banks (guilds and their bank components won't be saved). After the server's closure it will be impossible for you to transfer your guild bank stuff by using control panel. Items in your personal bank and Void Storage will be saved.
- After the transfer your gold amount will be reduced to 20000 (the rest of the gold will be gone on one character).
As for Cataclysm x175 realm
- Note that particular things (currency, items, arena teams and so on) have been changed or even deleted in the Mists of Pandaria, because you can lose them.
- You will have to learn your class specialization, glyphs, talents and some skills (for example, riding). Professions will be saved, but you will have to learn them again.
- Currency will be converted the following way: conquest points -> honor, valor points -> justice points. Honor and justice points will remain untouched (also, don't forget about maximum amount of currency allowed on one character).
- From today until this server's closure health points and damage will be increased for all creatures. All ratings will be lowered as well.
Sincerely, server's administration.