The rule on transfers is that you can't start out on a PvE server, and transfer away to a PvP server. Blizzard has said that players can't fight carebear up to 70, and then jump over to gank lowbies-- if you want the ability to kill those below you, you have to be killed first.
That is, unless you're friends with the developers. Players are claiming that someone named Broodthorn has been switched from Zul'jin (a PvE server) to Black Dragonflight, a PvP server. How do we know they're the same? The old Broodthorn's Armory profile is empty, and the new one is right here. All indications are that he switched servers, sometime recently. How is this possible? Broodthorn is now in Fires of Heaven, which is the same guild that Furor used to lead in Everquest. And Furor is none other than Alex Afrasiabi, one of Blizzard's main quest designers (he appeared on the Lore and Quests panel with Chris Metzen at BlizzCon). So bottom line is that if you're a good friend of the developers, Blizzard can make anything you want happen in game, even things they've specifically said shouldn't happen.
And this isn't the first "stealth transfer" to go down, either-- supposedly, entire guilds have been transferred from server to server by Blizzard before. Sure, Blizzard has the right to do something like this (it's their game, their rules), but it's a little hypocritical (at least) to require paying customers to abide by certain rules, while moving your own guild around at will.
Update: Wow. To tell the truth, I was tending towards the camp of "it's a perk, who cares," but Nethaera is having none of it. After someone linked this post on the forums, she sez:
This transfer was based on an internal request that bypassed our checks and balances dictating how such transfers occur. Since the transfer violates our character-transfer policy, the character in question is being moved back to its originating realm, and we have imposed some additional measures to help avoid such situations in the future. We made this correction as soon as we became aware of the oversight; we appreciate everyone's attention and input on the matter.
Hardcore. Way to go Blizzard for making everyone play by the same rules. Kudos.