Microsoft have revealed that they are planning to announce something later today. The company have issued a press release that says the company plan on announcing something, with host Steve Ballmer. Many are expecting Office 2013, but at this point it could be anything.
The announcement will be available on live webcast, and will begin at Noon PDT. This announcement could mainly be focused on Office 2013, as it has recently been rumoured that an Office 2013 public preview was expected to launch on 16th July. Only time will tell.