Even at $300, the total cap is still under 25 billion dollars. If SINA is Chinese Facebook, the company is worth much more than that.
This week the general market may suffer the long due 10% correction. But I predict SINA will not be down more than 5% and it is the great buying opportunity unlike AAPL, GOOG, CSCO and INTC. These American companies have seen short term and medium term top IMO.