Blizzard has announced that Starcraft II expansion pack Heart of the Swarm has now entered close beta status. The developer says the first round of lucky participants will include pro gamers, members of the press, shoutcasters and Arcade contest winners but there are plans to open the multi-player only test up to more players soon.

Gamers interested in participating are advised to opt in by clicking on the 'Beta Profile Settings' under the account management section in your account. Of course, opting in doesn't guarantee you will get beta access but you can better your odds by actively playing StarCraft II using the same account.

Blizzard points out they are also working with several fan sites and community personalities to provide additional opportunities to gain beta access. We suspect participating sites will be listed on the StarCraft II fan site so be sure to keep an eye out there as well. They didn't say exactly how many beta invites will be handed out; only that they would add more players as required for their testing.

The company looks at a number of different metrics when traditionally selecting beta testers including system specifications (and a bit of luck) and whether or not you are actively playing the game in question. Participation for the beta is open to both Windows and Mac users simultaneously in all regions although supported languages are limited to English, German, French and Korean.

Last but not least, participants aren't binded by a non-disclosure agreement so we'll most certainly be seeing a lot of content from the beta.