I'm a big believer in writing short blog posts.
A blog post isn't supposed to be an article, it's not supposed to be a place where you write thousands of words of text to try to get across a complex point.
Blog posts are meant for quick ideas, for stream of consciousness type thoughts that introduce an idea or flesh out an idea, not to provide an exhaustive discourse on that idea.
People don't visit blogs to read articles, they visit blogs because they value the thoughts and ideas of the blogger and want a quick insight into what he or she is currently thinking about or working on.
Not that they wouldn't be interested in reading an article or ebook written by the blogger at another time, that's just not what they're thinking about when they have a minute or two of free time and are checking their RSS feeds.
If you do have a lengthy topic you want to cover for your audience, use the post to whet their interest in the topic and cover it in more detail in a separate article or ebook which you then link to from the post.
Remember that most of the people reading your blog are there because they want a quick read.
Give them that quick read and provide a link to more information for those who do have the time and for the rest to come back to later.
Listen to your audience and write short posts.
Show that you value their time.
If they know that your blog provides useful information in easily read chunks, they'll thank you for it by visiting more often and therefore giving you more opportunities to market your thoughts, ideas, and products to them.
(Another very powerful technique that I'll address in detail in a future article is to use your blog to float a "trial balloon".
You then use reaction (in the form of comments, links in, and trackbacks) to that post to gauge the interest of your audience or your industry in a particular topic or point of view before you invest the time and energy into writing a more lengthy article or ebook about it.
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