Choose a niche based off of what you are interested in, something that you will enjoy writing about and researching as you develop it. Even though there are already tons of niches being done already, there are billions of people online, and surely more than enough people to go around and be an audience for your niche. Keep in mind that there is variety and competition everywhere. I assure myself that my niche will succeed because look at business and or stores today, such as CVS and Walgreens, yet we all don't go to just one of them. Some go to both or perhaps one if they're a die-hard CVS fan, or some may go to Rite-Aid, or etc... I hope this helps, good luck on finding and choosing your niche! :)

You should start by making a list of your hobbies and interests. Look at things that you would act on, read about, study/talk about daily. Bearing in mind that you should be able to write/study/research about it on almost a daily basis, choose the one that you are most passionate about. It helps when you make your passion into your job! Cheers, Jerry