Aug 13, 2010 07:15 GMT  ·  By

The next major iteration of Microsoft’s browser will reach the Beta development milestone on September 15th, 2010.

The company confirmed the date officially as it started sending out invitations to members of the press, but also developers and designers for the Internet Explorer 9 (IE9) Beta launch event in mid-September.

With IE9 hitting Beta, the software giant is gearing up to celebrate the “Beauty of the Web” in San Francisco on September 15th.

The “Beauty of the Web” website is already live, and comes with a small puzzle that can be resolved by typing “native.”

Only after visitors complete the Internet Explorer 9 “Unlocking the native web” puzzle are they redirected to the R.S.V.P. page for their invitation.

“Starting today, a select group of VIP web developers, designers, bloggers and press begin receiving their invitations to an event we’re holding in San Francisco on September 15th to celebrate the Beauty of the Web and to mark the launch of the IE9 Beta,” revealed James Pratt , IE senior product manager.

Users can also check out the video embedded at the bottom of the screen in order to get an idea of what the “Beauty of the Web” site is all about.

If they are to visit the site in question they better do so by leveraging the latest Platform Preview Build of IE9.

“Reception for IE9 has been very positive since MIX with over 2.5 million downloads of the platform previews. The most recent platform preview – our 4th – was released last week,” Pratt added.

“Since space is limited at the event and not many invites have been sent out, I captured what the invite process looks like so everyone could see.”

“Invitees get an e-mail invitation with a link to a special HTML5 website. To RSVP, they have to complete a word puzzle by typing the letters shown on the screen: Unlock the _ _ _ _ _ _ web. The letters they have to work with are V E A N T I and the solution is a single word.”

“Once the puzzle is complete, the RSVP button appears so they can RSVP for the event,” Pratt stated.

Internet Explorer 9 (IE9) Platform Preview 4 is available for download here.

Follow me on Twitter @MariusOiaga.

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