We are currently running rails 2.1.
My main motivation for the upgrade is the fear that gems/plugins will get rarer/unavailable/unsupported day by day for our version (,and the excitement of the latest technology).
I understand there are many-many improvements that come with rails3, but probably what my manager would want to listen is the advantages that he'd get, in terms of the business.
Ours is a Saas application, load on the app is not very high, but the demand for reliability is more.
Edit :
Looks like my inclination towards the upgrade needs rethinking, so answers to "should I upgrade" are welcome.
my original question also needs answers - how to describe the business advantages of an upgrade from rails2.1 -> rails3.
The app is under active development/enhancements.