Hi! My name is Jordan and I'm a USDSer at the DoD. I'll be sharing my experiences trying to open source software within the DoD at the upcoming Mid-Atlantic Developer Conference in Baltimore (Aug 1-2). As Robbie mentioned, some of us also participate in many of the user groups around town, including DCJS and Women Who Code DC.
Seems like these tools are still evolving, wondering how long it will take for these to really be adopted in enterprise orgs (thus fueling more growth).
I'd agree that Node.js is pretty dang nice for RESTful APIs. The fully asynchronous nature means really great throughput on the server, especially when most of your processing time is spent in DB or file I/O (as is often the case in APIs). As for disadvantages... I dunno. I guess if you don't really know JS very well it could be difficult to get into, and good developers are harder to find than in some other languages. But as a platform for APIs it's pretty solid.
Or just require devs to use --harmony. I think there are a couple modules that do so... like koa. :)
Of course, since that's basically "experimental" I guess people would think your module is also "experimental". But I think let and const are pretty darn stable.
