tbh if I release something and someone else releases something better (either if he had ideas that I didn't come up with, or if he could make something that I wasn't able to figure out), I'm happy for them. Of course if they use some of my work I expect them to mention it. I don't expect 1 dev to come up with all the ideas etc by himself, so if I make something that someone else can use for a great idea or improve upon it, I'm happy - because in the end it just ends up in better profiles/CC's/whatever.
I believe in working together to achieve great, instead of competing. It's not like a company where you need to compete to improve your income, is it?