Fixed that for you.
Want to play Wintergrasp? You will be instantly killed by 20 chain lightnings at once.
Want to try and get the "For the Alliance/Horde" achievement? All it takes is one Multiboxer to log in his chars, walk in the middle of your group while unflagged for PvP, then instantly kill half your group with 1 spell..
Want to play Battlegrounds? Same as above, whichever faction has the mboxer wins.
Warmane endorses multiboxing. See their multiboxing forum here: http://forum.warmane.com/forumdisplay.php?f=189
It's a unique strategy of gameplay, basically it involves paying to donate on multiple accounts and then using 3rd party software to control all your characters simulataneously.
If any player is able to kill your army of characters, clearly you don't have enough. Just buy more.
World PvP is usually decided by whichever Multiboxer paid for more characters. The pathetic normal players just run around having zero impact next to 50 shamans acting in unison with hundreds of totems.
Edit: Multiboxing on retail was far less effective, as you had to pay to maintain the subscriptions for every account. Here you can just make as many characters as you want and nobody will even try and stop you.