There were lots of medias got an invite from Microsoft in the last week about an event in Los Angeles in June 18th, but seems nobody got detail information about this event, nobody knew what Microsoft will publish before today.
However, about the noon of today, some media got some updated information but, still no detail:
Microsoft has finally released the details of its much-hyped media event: The invitation-only news conference, where the tech company is expected to debut a tablet device, is scheduled to take place at Milk Studios in Hollywood on Monday afternoon. — from latimes.com
Anyway, there are some websites will provide live reports, like this one: