As I said, lots of people are doing online backups. Nobody else is doing secure online backups.
Building a secure system is a hard problem
Exactly -- that's why it's something which I can do but nobody else has done yet.
and [...] few people can judge how well your (sic) doing
Fortunately, with a doctorate in Computer Science, as the FreeBSD Security Officer, and as "that guy who found a security flaw in Intel processors a few years ago", I'm ideally positioned to show people what I'm doing right -- and what everyone else is doing wrong.
Is secure online backups a smaller market? Absolutely -- most people don't care about security. That's the price you pay for entering an arena where there are many established companies: The best strategy is to carve off a smaller part of the arena rather than trying to fight for the complete arena.