Well, the market expected a not so impressive earnings. Therefore, the downward movement had taken place already over the last week. The earnings wasn't anything better than what the market expected. Therefore, the upside is limited. The critical part is the guidance. The projected revenue for next Q is lower than many had previously predicted. As such, the stock price should have more downward pressure now.
The quarterly results might not have been too bad, but the guidance, which is what matters, is not too good! The projected revenue for next Q is lower than many previously had forecasted. There's no reason for the stock price to jump above 500 under this condition. Chances are it will stay sub 400 for a while.