XBLinJS 0.4 is released now.
One of the side effects of this big change is that XBLinJS can now actually be used as a replacement for XBL; see the Advanced Uses page.
This is probably the last release for a while, unless I get some kind of feedback, because I am going to turn my attentions back to my Iron Lute project, and start a new job in the near future. How much this library changes will depend on feedback or if I quickly start using the new library in my new job.
If anyone wants this feature sooner rather than later, or would like to work on implementing it, contact me and I'm sure we can work something out.