Blizzard has announced that they will change your character's name to an available, allowable name for $10 and I say, "It's about time!". This is an administrative service that should have been available from the beginning, in my opinion. Regardless, it's available now (on selected servers) and here are the rules:

• It's $10 per name change.
• You can't change your name again for 90 days and your old name will be unavailable for 90 days as well.
• It has to be available on your server. Captain Obvious says, "Duh!".
• It will take a few hours while they approve your name change, since it must follow the Naming Policy.
• While the name change process takes place, your character will be unavailable.
• The name change is permanent unless you pay to change it again 90+ days later.
• This function is being rolled out in phases, a few servers at a time.
• Characters on your ignore list who have had their names changed will remain there with the new name. (Update: edited for clarity)
  

Blizzard has a FAQ page setup on their Support Site if you have more questions. If this is something that interests you, go to the Account Management page and select Paid Character Transfer (you will have to login).

I actually like my character names, but I reserve the right to change my mind at any time and I'm glad I now have the option.

The official forum announcement with the list of the first phase of servers is after the jump.