Well, if you are using another article, do NOT copy and paste that entire article into your blog or you will be violating copyright law. Use a paragraph, then link to the original article.
You want your blog to generate lots of 'google juice'. You need to write a blog that is titled, tagged, and written with Google and other search engines in mind - but write it so that a reader will be interested and engaged and will want to come back.
An excellent book to start with is
Realty Blogging.You need fresh, original, engaging, and relevant content. Or you will just be spinning your wheels in the dirt, going nowhere.