At times it seems that there are a never ending amount of topics to choose from, sometimes there can be lots going on in your industry, whilst at other times it can seem that there is nothing new to write about without just rehashing what everyone else might be talking about.

One source of ideas for blog topics can be to look at the "long tail" phrases that you perhaps do not rank as prominently as you would like for.

You can do some keyword research for this, in the same way as you might when deciding phrases to target with organic search, to ensure that you are targeting something that people might be looking for. This may not work for competitive phrases however, as these are difficult to establish rankings for, but specific topics from within your industry can be ranking prominently very swiftly, perhaps even within minutes or hours!

What I would always ensure is done, is that you ensure that the keyword you are targeting is in the Title of the blog and permalink. These are really strong factors in getting your blog ranking for a particular phrase and you should ensure that these are "optimised" to the fullest extent.

It's also a good idea to contain a relevant link on your blog. I've blogged in the past about the need to link to pages from your site within your blog, as this content is often stolen and used elsewhere, so you may as well get some benefit from it being stolen, but there are also valid reasons to link out externally to relevant sources from your blog.