Hi,
I've recently took on refurbishing the hdf5.node project https://github.com/ryancole/hdf5.node
It is now compatible with hdf5-1.8.12, nodejs <http://nodejs.org/> v0.11.13-pre and V8 <http://code.google.com/p/v8/> 3.25.30 development versions. there has been a big change with the V8 native interface and this project is refurbished for V8's current status and not being made backward compatible before all the sawdust.
Particularly I'm exploring the hdf5 high level interfaces since they're making sense to me. The hdf5 c++ is used natively too for the file and group objects and metadata which need some persistence during the io of h5 data.
Still at early stages and experimental; if anyone has any design and interface ideas I very much would like to have your input.