The latter has probably been promoting an active community since the early days it was the first ever project I became involved with and sharing your contribution with fellow users is a very powerful motivator if it's done well. By this I mean feeling you can contribute in the first place, I had never used PHP and 'hacked' the code to create something that worked and then uploaded it and it amazed me how people took my effort and cleaned & polished it, I was given pointers and help which again make you want to get more involved.