Chrome is renewing work toward a Bluetooth API for websites to communicate with devices. We have started work reviewing existing APIs, use cases, and security concerns.
[1] has a start of that work focusing on minimizing the device attack surface exposed to malicious websites, possibly by removing access to some existing Bluetooth features that are hard to implement securely. We'd also like the API to support a user interface to select and approve access to devices as opposed to using certification and installation. We have proposed a Community Group [2] to incubate this specification, and are soliciting supporters! [1] https://github.com/jyasskin/web-bluetooth [2] http://www.w3.org/community/blog/2014/07/30/proposed-group-web-bluetooth-community-group/