Heh, just noticed you work for Blockchain Ltd. I may have been a bit nicer in my last comment had I noticed. Anyway, it's worth noting that your users are still vulnerable to a Lavabit-style seizure (or hack from anyone) of your private keys, with the intent of pushing out modified JS to seize coins or track users. It's my understanding that the purpose of the Chrome extension is to prevent tampering[1], but if the authorities are really serious, they could also coerce/compromise Chrome Web Store into putting out a malicious update, signed by your seized private key.

Which authorities and laws is the company subject to?

[1] https://blockchain.info/wallet/browser-extension