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Mark, The Moz tools offer some excellent competition comparisons. You can create a campaign, input keywords to track and follow competition. The tracking shows DA, linking C blocks, etc. and will track on a line graph how your site is doing against the competition. As far as selecting an industry or niche, this will take lots of research. My suggestions would be to find something that you're knowledgeable or passionate about. This way you have lots of content you'll be excited about creating. There are many things you need to consider when selecting a keyword to go after. But in your situation i would tell you to look at these two, keyword competition and indexed pages for the keyword. This will help you see how much competition there is for a specific niche. There's lots of tools you can use to get more information, and if you're going to go forward with launching a site do your due diligence and research. Good luck to you. Chris Adficient.com