WoW Discovery?

[EverBlue]

They are not illegal in that no municipal, state, or federal law enforcement agency will prosecute you for them. But they are against the Terms of Use. Here's where to find the TOU: http://www.worldofwarcraft.com/legal/termsofuse.html

Here's the relevant text, in section Four A.

Only Blizzard or its licensees have the right to host the Game. You may not host or provide matchmaking services for the Game, or intercept, emulate or redirect the proprietary communication protocols used by Blizzard in connection with the Program, regardless of the method used to do so. Such prohibited methods may include, but are not limited to, protocol emulation, reverse engineering, modifying the Program, adding unauthorized components to the Program, or using a packet sniffer while the Program is running.

That part explains that you can't do what private servers are doing. This next part explains how you can't modify your game to access private servers. It's section Four B.

You agree that you will not (i) modify or cause to be modified any files that are a part of the Program or the Service; (ii) create or use cheats, bots, "mods", and/or hacks, or any other third-party software designed to modify the World of Warcraft experience; or (iii) use any third-party software that intercepts, "mines", or otherwise collects information from or through the Program or the Service. Notwithstanding the foregoing, you may update the Program with authorized patches and updates distributed by Blizzard, and Blizzard may, at its sole and absolute discretion, allow the use of certain third party user interfaces.

Private servers are a great way to get your account banned, the changes to the game files are apparently easy to detect.

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