RoR 2.3.5

If you can, upgrade, especially if your app is developed for Windows. I have developed several apps in 2.x and they are increasingly becoming a nightmare to maintain. Most of the better gems I’ve wanted to use work only under Rails 3 and the alternatives are usually not good. I am currently upgrading an app from 2.3.5 to Rails 3 and although there are challenges there has been nothing I couldn’t do easier and better in Rails 3, which has helped to clean up the code quite a bit.