One big feature that now exists is that anyone can create fork the uPortal git repository, make some set of changes on the fork, and then request those changes be pulled back into uPortal. Think of this as "submitting a patch" on steroids. For anyone that is interested in learning more about git the links in the Additional References section below are quite valuable.
A proposed workflow for the project and documented in the wiki: https://wiki.jasig.org/display/UPC/Git+Workflow
There are a few workflow options, the direct merge option is only applicable to uPortal committers but the Pull Request option is applicable to committers and anyone else that is interested in supplying patches to uPortal via GitHub Pull Requests.
While patches supplied via Jira issues are still a great way to contributed Pull Requests are even better, they allow VERY easy review of the changes and how they merge and it just takes a click from any uPortal committer to perform the merge.
For those still getting to know git this is a great reference: https://git.wiki.kernel.org/articles/g/i/t/GitSvnCrashCourse_512d.html Git really is a bit of a paradigm shift from SVN and while we'll have our bumps for the next few weeks I really think it is going to turn out to be a valuable move for uPortal.