When setting up a blog how important is it REALLY to stick to a niche topic? Is it just hype? Can you still see search engine results by writting on a variety of topics?

Yes you need to find a topic and stick to it, if you want to make money. Google's automated systems look for your keywords (the words most often used in your blog) to decide what your blog is about. If you're jumping all over the place, Google won't be able to see any frequently repeated words, and your blog won't appear in search engines - so you'll get no visitors.

Similarly, your blog will get no traffic unless you promote it. If you stick to one topic, you can join forums about that subject, visit and comment on other blogs about that subject, etc. If you have lots of subjects, you'll have to spread yourself thinner and the result is you'll promote less effectively for all of them. Result = fewer visitors = less money

yes it is very important to for your blog to related to the niche topic because, it will increase your content and likely being searched often. But before writing articles you need to research your product, niche, and keyword research.

http://hubpages.com/hub/Successful-Niche-Marketing

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