Phusion Passenger 3 Released: The Next Gen of Ruby Webapp Deployment
Phusion's Passenger is the de facto way to deploy Ruby based webapps (a statement backed up by Hampton Catlin's Ruby Survey) so if you haven't yet made the jump, 3.0.0 provides a good excuse. It's as stable as ever but there's even more performance and a ton of new features, as covered in Phusion's four "technological preview" blog posts.
RVM users will also be happy to learn that it's now reasonably easy (and I say "reasonably" because you'll still need to do some reading) to deploy Passenger to cover multiple Ruby versions.
Installation and/or upgrading
Not using Passenger yet? Already running a vanilla Passenger install? Both installing and upgrading are easy (though you might want to try it in development first before going nuts on the production boxes) and work in the same way. First, install the gem:
[sudo] gem install passenger
And then run the regular installation script for either an Apache 2 install or an Nginx install (it'll install Nginx for you if you haven't already got it):
In both installation and upgrade cases, the above scripts will provide more details on what to do next (in Apache's case, it's usually as simple as copying and pasting some configuration entries into your Apache config).