Even centralized version control began the distribution of control. At least, it made it easier for more than one person to control the changes of a codebase. In old days of e-mailing patches around, it was pretty much a requirement that a single person be responsible for the merging of patches into any single codebase (or any section of that codebase). Source control allowed multiple developers to commit changes and began to put less burden and less power in any one person's hands.
Anything that makes the submission of new code easier is going to thin that power even more. When anyone can come along and submit changes to change functionality or add something new, it takes a little bit of control away from the owners of that project. At some point, you start to feel that the community runs your project as much or more than you do. This has its good and its bad sides, but it is a shift we see more and more.
A few years ago there was a rift in the development team of the XFree86 project and from this we got our current fork, X.org. The story is well known and it brings to light an important political power of open source: fork and run. Even if you own a project, you'll begin to loose power both to make users and other developers happy, and to keep control at all. A strong enough disagreement could mean everyone else just leaving you behind and taking the project with them, under a slightly different name and a forked codebase. This can be scary and obviously could be harmful, but like any democracy we trade that for the benefits willingly.
Today, forking is easier than ever. Project hosts like github and launchpad promote forks as the primary means of submitting patches. No longer do you submit your changes for scrutiny and wait for acceptance or denial. These are the days of "I liked your project, and I have my own version of it. Take it or leave it." Other developers are as welcome to use your version as the original. This begs the question, when does the original project stop mattering and when do we come to realize that all forks are created equal?
The big question here is when the use of a fork with a few patches, either yet to be pulled into the original or rejected for differences in opinion, becomes as reputable. This can only happen if we can get past looking at forks as either replacing or diverging and understand them as ongoing versions with differences for good reasons. Should I find that I want to make some modification to a library I'm using that the current maintainer doesn't want to accept, there should be no social issue with those two branches, the original and my own, existing and being used in parallel. The choice for others on which to use can be considered of as much weight as its configuration options.
When we reduce to zero the social cost of taking a project for you own to make the changes that fit your needs, we make many things easier. Abandoned projects become far easier to adopt, without feeling the need to make all due process to contact and get the fair wishes of the creator. Difficult to work with maintainers no longer hold control over users and developers who disagree, because even more democratic than a democracy we can allow everyone to truly get what they want.