Comment Simple Answer: Stay ahead of the pack. (Score 1) 729
For instance, Adobe has nothing to worry about. There's not going to be any Open Source project that can compete with Photoshop anytime soon. If the stuff you're writing is that easy to implement that every addition or extension is being copied, and is "just as good" as you say, then the issue is with the code you're writing.
The Open Source devs trying to mimic your extensions should be sitting back saying to themselves "how the hell did they do that?" and by the time they figure it out, you've already got new features that they don't.
Also, providing support seems to be the best way to monetize Open Source. They may provide similar functionality, but you can offer custom tweaks and support for a fee.