This is pretty good as far as holiday season giveaways go. You need to act between the 15th of Devember and the 31st of December in order to qualify and, of course, you need an Xperia smartphone from Sony Ericsson.
The basic Box account gives you only 5GB for free.
Seems to be good to be true – unless you don’t have a Xperia. If you’ve done it right, logging in via the app, you should get this message.