I just (okay, a few days ago) released version 0.2.0 of btle.js to
npm. This has a bunch of API changes - the connect method now gives you a
Device object, instead of a Connection. All the ATT methods are now on the Device object, but, in addition, you can
access all the GATT functionality by querying the device for services, which returns Service objects, and services for
characteristics, which return Characteristics objects.

I'm also working on API docs for the whole thing.

Well, I published my Node.js module for Bluetooth LE, btle.js (pronounced "Beetle Juice") to npm. Even though it's labeled version 0.1.0, it's got most of the functionality that's necessary for Bluetooth LE - reading attributes, writing commands and requests, and listening for notifications. I'm hoping to add more functionality over the next few weeks/months.

The main reason I was doing this was to get my TI SensorTag working with my Raspberry Pi and Bluetooth LE dongle, which it now does. I've even got the beginnings of a Node.js module for the sensortag,