Our site is currently using Joomla 2.5.27 and Civi 4.4.11. We need to either upgrade Joomla & CiviCRM to the latest or migrate our site to a drupal platform. Both sound like a lot of work. But we have some kinks in optimally using Civi that appear to be the result of incompatibility w/ Joomla. I am not a developer but am a knowledgeable user; I have some tech volunteers who are prepared to help me once I make a decision. Any thoughts?
Developers tend to prefer Drupal over Joomla. But each CMS has it's pros & cons. You need to figure out which one is better for you.
For example if you have a Joomla extension that gives you functionality which would require a lot of custom coding in Drupal, it would make sense to stay with Joomla.
The kinks you mention may not be around in that later versions of Joomla & CiviCRM, but there may be others, so you really need to do some testing to make a decision that's right for you.
Demos are available at: https://civicrm.org/demo - but they are reset periodically so you may prefer to create a sandbox on your own server or local machine for testing.
The big advantages that we typically use with Drupal are
Views: the ability to build query/displays that can be used in many different settings
Webforms: ability to push/pull data from civi in a form building tool that has a lot of extras
CiviCRM Entity: means Drupal can see/use CiviCRM data as if it is a Drupal Entity.
Whether it is 'worth' the effort is harder to judge as that would depend on what you have in the CMS and how easy it would be to rebuild that in Drupal. The Joomla to Drupal migration/conversion process has worked well for us in the past.
If we had a client on old Joomla, and if upgrading Joomla would involve rebuilding theme, rethinking content types, etc, then we 'would' migrate to Drupal. But that is opinion/preference, not a 'solution'.