[bityard]

From where I sit, the primary distinction seems to be where the fork lives. On Github, forks are public. You get a copy of the repo in your own namespace on Github which you can pull from and push to from wherever. Others can see it and any changes you make to it as well.

On OpenDev, your clone/fork/personal branch is only on your dev machine and you only push patches, if I'm reading it right.

I guess the OpenDev model discourages people from forking the repo, modifying it to suit their needs, and then not sharing the results. To some degree.

I think I actually prefer the GitHub model where people's branches/changes are public by default unless they choose to go through the trouble to make their fork private. I have found many good bug fixes and enhancements for repos abandoned by their upstream authors this way.

[cmsj]

The key philosophical difference is that in Gerrit you are proposing a specific change, where in GitHub you are proposing a branch be merged.

It's a very subtle distinction, but having worked on OpenStack in the past, I much prefer the Gerrit model. Patch revisions are much easier to track over time than pushes to a PR branch during review.