Sitecore recently released version 8.1, even without xDB there are some new exciting features introduced for example the new language fallback features and fully integrated IP Geolocation services. A more detailed list can be found here.
When you do not have xDB enabled and are upgrading from 8.0 to 8.1 then there is one setting that you will need to correctly update otherwise a number of things will most likely break without any clear indication what the root cause is.
In Sitecore 8.0 you had to follow this guide and disable the Analytics.Enabled setting. It is easy to assume that the same would apply to Sitecore 8.1. However in Sitecore 8.1 you’ll have to set CMS only mode by setting xDB.enabled to false in Sitecore.Xdb.config. You can verify xDB is correctly disabled by looking in the Sitecore log for a message like this “1234 17:21:20 INFO xDB is disabled.”
Hopefully this will help someone. Apart form this I found upgrading from 8.0 to 8.1 straightforward.