Because everyone knew that they were going to miss estimates, they just didn't miss as badly as expected. Estimates that you see do not always accurately reflect what the street is thinking and without being in the loop and talking to other managers, some of these stock reactions look irrational and confusing when in actuality different expectations were baked into the stock. Analysts follow the herd mentality and will usually not stick their necks out.
This "puppy" is up because the company did what they said they were going to do. It's a conservative company, they provided estimates and they meet those numbers. Also they like the sound of you shorts pissing on yourselves.
I also think many fund managers may have wanted to own this name but knew bad news was coming. And many funds have to own some tech, and this one has a future, and a product cycle. Even if it goes down a little further, the chances are it will be higher in a couple of years - which isn't such a certain thing for many of the tech names. So relative downside is probably good, and upside probably assured - if anything is these days. fwiw