I can't say I'm a massive success or anything. But I think it depends entirely on your approach and exactly what you are aiming to get out of it.
I'm not really too fussed about earning money, so I don't write the typical articles of how to use keywords and using SEO for articles and how to earn money online and all that. I just write about things that interest me and that I hope are of use to some people out there, even if it is often a niche or a small number of people, as those are often the things with fewer resources anyway!
My advice would be to stick with it, write about what truly interests you and stuff you think might be of value to someone, and get involved throughout the site. I quite enjoy answering questions, browsing forums and other people's hubs. However if your main reason is for a significant income or similar then hopefully someone who knows more about that will answer your question too! Also there are plenty of hubs on that.
Good luck with whatever you decide! =)