Micro niche is a strategic and potent strategy to go into and ultimately to dominate a market with the minimum amount of effort. Once you start to dominate a mini niche you can focus on other niches in the identical niche and eventually pursue the niche itself. That would result in lots of free organic search traffic for your targeted niche and all the mini niches.
By focusing on all of the mini niches within a particular niche over time you will find that you simply start to rank in the search engines for the niche itself, effectively killing two birds with a single stone.
http://iconnect-people-search.com/micro-niche/what-is-micro-niche