Box.net Raises $50 Million From Salesforce And Others

I'm still trying to wrap my mind around what makes Box so special. Is there anything behind it that a hand full of us couldn't replicate on the amazon cloud in an afternoon with a couple laptops and a pot of coffee?

Plus, isn't the file sharing market going to be shrinking as more of these documents are going to be created and collaborated on in an application native to the web?

And the Google Drive stuff that got leaked?

Salesforce/Marc have made some good investments with Heroku, Mashery, and a list of others but I'm not so sure how long box can keep this up. I know they're hiring aggressively though.