While all of the discussion over the last few months has been about SAP/SuccessFactors and more recently the Oracle/Taleo deal, LinkedIn has been quietly going about the business of making money.

After the hyped up IPO there was a lot of speculation that the company was overvalued and no way it could meet expectations and the stock suffered. But with a very strong fourth quarter the stock price has been boosted and is approaching $90/share again.

The question is: Can LinkedIn sustain this type of performance?