Competition from Bing, Yahoo, and others has slowly eroded Google's sizeable lead in the search engine market throughout 2009, but recently released data suggests that Google is regaining its dominance in the SEO market.
Technical SEO is as important as in-content SEO. Adding things like a table of contents and reading progress indicators are a nice touch to help with page navigation. Always aim to develop content that is useful to your readers. Research what topics are of interest and what type of content they want.
Ensuring your blog pages and the content is SEO-optimized is a number one priority, but beyond that, there are some additional things to consider that make great blog posts. Spend a bit of time on keyword research before you start developing any content. That way, your blog will already have a head start. Make sure you use language that is clear and concise in plain English.