True. I don't use my Dropbox for any file hosting other than my Work Files, pictures, and some important backup files. The fact that Mega is using this encryption has me intrigued.
Meh, as pointed out in the Hacker News thread ... it's all for plausible deniability on the company's end - not real, personal, encryption of your files. YOU should be employing a private/public key system on your files if you would like personal encryption for anything you upload.