Finally got a chance to play with the Onion Omega I pre-ordered and was disappointed to find no NodeJS support.
No opkg and I see information on the web site about the release now being TBD. Any updates on those dates? Purchased expressly for the NodeJS support and without it isn't super useful.
I was actually googling around myself this morning for the same question. I did find this article which shows some success with getting node (almost?) working on the Omega:
Probably not the official answer that we are both looking for but may be something to try out...