We use git at https://bugs.launchpad.net/evergreen and offer access to the "working" Evergreen repository to anyone who sends in an SSH key. We ask that you create "topic branches" based against master for each feature you want to contribute and keep them separated, if you can. Also, please open a bug at bugs.launchpad.net/evergreen and point at your branch when you're ready to have it reviewed. More info on how we use git at http://evergreen-ils.org/dokuwiki/doku.php?id=dev:git
Should we submit our changes back to the community as a bulk patch to the current version or would it be more applicable to submit each change we are making independently?
The *ideal* situation for the community would be for your developers to check code into a public Git repository and work in feature branches based on the Evergreen master branch. You would presumably be able to get the most rapid feedback from others in the Evergreen developer community that way, too. Patches work best when applied against master as opposed to diffing against a release directly.
What IDE do you all use for working with and debugging Evergreen PERL code? Eclipse, Komodo?