Facebook posted good fourth-quarter results yesterday.
Facebook is a great company, with a great management team, and a big long-term opportunity. Facebook is growing at a very healthy rate, especially relative to most big companies. And Facebook still has lots of "platform" opportunities that may lead to big revenue opportunities in the future.
If investors are willing to bet that, at some point, those platform opportunities will unlock a huge revenue engine that will cause Facebook's revenue and earnings to skyrocket, then investors can certainly buy the stock at this price (just north of $30).
But, otherwise, there's just no obvious reason to do it.
Yesterday, after reporting good Q4 results, Facebook announced that expenses will grow much faster than revenue in 2013.