There shouldn't be long to wait now, as Activision has today confirmed details for the PC version.

All current and new users who are register on Call of Duty.com will receive a beta key that will allow them to create a profile in the game.

Activision explain:

So while username / passwords will not be required to play our game, you will have globally unique profile names.

Why are we doing this? Because also for the first time ever in a Call of Duty PC title, we're bringing Friends and Invites (which are typically console staples) to the PC. So we have built-in Friends functionality. You can add friends, filter your servers by Friends (see which servers your friends are playing in), join their servers, etc. You can also invite any online friends to come join you in your current game. We didn't want the new Squad mechanics we've developed to get watered down on the PC, which is ultimately why we decided to bring you Friends & Invites, and thus globally unique profile names.

Now we understand that clan tags can change frequently, and it would be obnoxious and not very user friendly to keep changing your profile name. So we've added in clan tag prefixes, which will show up in-game. This should allow you to take full advantage of our Friends & Invites features, and still be able to make yourself more uniquely identifiable in-game.

It has also been confirmed that we will be able to host our own servers, whilst GSP's will be able to sell BETA servers and put up as many dedicated servers as they'd like. All of this will function as if it were a regular Multiplayer game. It's important to note, that for the BETA, the dedicated server will be Windows only.

Gamer profiles will be deleted at the end of the bta

Now all we need from is a start date!

Register on Call of Duty.com