Live: Facebook news conference at 10 a.m. Facebook is holding a news conference on Tuesday at its Menlo Park, Calif., headquarters, above, to make a mystery announcement. David Butow / For The Times / January 14, 2013 January 15, 2013, 7:00 a.m. MENLO PARK, Calif. -- Anticipation has been making Silicon Valley wait just like a Carly Simon song in a 1970s Heinz ketchup commercial. But that wait will come to an end Tuesday morning when Facebook holds a news conference at its Menlo Park, Calif., headquarters. Facebook last week invited the media to "come and see what we're building." It provided no details. There has been no shortage of speculation on what Facebook might announce as investors pushed shares above $30. Shares closed at $30.95 on Monday, though analysts say the stock gains may have more to do with investors' anticipation of the company's fourth-quarter financial results due out Jan. 30 than anticipation of a major announcement at the mysterious news conference. The invitation drew so much attention because it's Facebook's first since the troubled initial public stock offering last May. Analysts say it's unlikely Facebook will make a major announcement two weeks before its earnings report. But that has not stopped bloggers and analysts alike from guessing what the announcement might be: a new iPad app, new advertising formats (definitely mobile, maybe video), new mobile features and, the longest shots, a search engine or a Facebook phone. In September during an on-stage interview with investor and blogger Michael Arrington, Facebook Chief Executive Mark Zuckerberg said search is a promising area of growth for Facebook. But most people expect Facebook to improve search on its website rather than start its own search engine. Zuckerberg downplayed speculation that Facebook would build its own phone to compete with Apple's iPhone and devices powered by Google's Android software. We will be live tweeting from the event starting at 10 a.m. Stay tuned.