Hi Phil,
Sorry, Rubber's not dead. But I'll wholly admit development has been slow lately. I've had some personal issues arise that have just made it very difficult to dedicate time. Rubber 4.0 is nearly complete and I plan on taking some time over the holiday to get it over the finish line.
It'd probably make for an interesting retrospective, but some other big things got in the way. I had been waiting on fog to release 2.0 and that just never happened, so I had to change some stuff around there. And then Ubuntu switching to systemd meant all our upstart scripts needed to be updated, but at the same time Rubber commits to supporting Ubuntu LTS releases, so I couldn't just drop it either.
Long story short, I'd expect Rubber master to work for you. And before the year's end, Rubber 4.0 will be out. With a much more solid base at that point, ongoing development should continue with much greater regularity.