Slightly off-topic: is learning Rails still a good career choice? I'm not particularly keen on JavaScript on the server and I think I am slightly tired using .NET on a daily basis.
There are plenty of stable companies out there running Rails apps and I'd venture a guess that a lot of start-ups probably still use it as it's great for small teams and rapid-prototyping.
On a side note, we also have hired devs who don't have Ruby experience but who are generally smart, experienced people, who know more than one programming language and are willing to learn whatever stack they need to for getting the job done.