First off, no. There is still no release date given for the Diablo III beta. However, it appears that Blizzard is in full swing in preparing for the beta. On August 1st, the same day as the press event release, Blizzard added a page to their site about Diablo III's beta. In fact, it was an announcement article. However, there has obviously been no actual announcement for the beta.
More importantly, Blizzard is asking that everyone who wants into the beta should update their beta profile settings with a new system check.
Official Blizzard Quote:
You can run the new System Check by visiting the Beta Profile settings of your Battle.net account:
I don’t have a Beta Profile
If you haven’t yet created a Beta Profile on your Battle.net account you’ll be presented with two download options, PC and Mac, for our System Check program. Running the program will present you with the Beta Test Opt-In Agreement, and once you agree to that it will immediately query basic computer specification information such as your type of video card, processor, and RAM. Clicking the Send button will then upload the shown information to your account.
On your Beta Profile page, you’ll want to ensure you at least have “Diablo Universe” checked for future testing, if not StarCraft and Warcraft as well. That’s it! You’re now eligible for future beta test opportunities.
I have a Beta Profile
If you’ve previously uploaded your system info you should use the links to download the new System Check program for PC or Mac and update your system info. Run the program, read through the Beta Test Opt-In Agreement that appears, and once you agree to that the program will immediately query your basic computer specification information. Click Send and the program will automatically update your profile with your system specifications. You’ll remain opted in for whichever beta tests you’ve previously selected, and you can change these selections on your Beta Profile page at any time.
Having current system specifications and checking the franchise boxes to express interest in beta testing our future products does not guarantee your entry into the beta test. We will grant a very limited number of people entry from the entire pool of those interested, based on their system specifications and other factors. While having an official Battle.net Beta Profile is one way to potentially get in, we’ll have information on other ways to increase your chances as we draw closer to the beta test.
A special thanks to evilenginen9 for sharing this information with us.