I do hope this is a joke. "some fancy acronym like AES"... I can't tell if this is a failed attempt to be funny through saying something so ridiculously stupid or if you're serious. There are lots of acronyms that are BS, but AES isn't one of them. It's mathematically backed and has been thoroughly tested to be strong.

Dropbox being a YC company means absolutely zero other than that YC liked their idea and supported them. That doesn't give me any assurance that they won't make a mistake or that an employee won't sell my data.

In fact, Dropbox, despite being a YC company, already slipped up majorly once to the point that every account was completely passwordless. You could just type in random emails at the web login and view some stranger's files. Story here: http://techcrunch.com/2011/06/20/dropbox-security-bug-made-p...

On the other hand, AES has yet to slip up. My AES encrypted data will take a significant fraction of the life of the universe to crack and, YC or no, a single programmer error won't break it.

Is a fancy acronym like YC any better? I would trust the founders not to look at private data, but any company that has employees is vulnerable to one of them going rogue.

Funny, but for those who don't get the joke https://news.ycombinator.com/item?id=5059806

YC doesn't control Dropbox. Whatever trust you have in a minor shareholder, it shouldn't translate to trust for the company.

There are other reasons as well: potential vulnerabilities in their software, malicious/crazy/corrupted employees, etc. Healthy need-to-know rule is enough to decide that if there's no reason your cloud provider should have access to your data, he shouldn't have it.