SEO and blogs can be best mates. Having a blog and posting to it regularly with interesting relevant content can add some great value. It works best if you’re blog is not sat on a subdomain, or even on another domain altogether.

For example a subdomain like http://blog.website.com looks like it might be bang on for the job, but for SEO it can be problematic- engines will see it as a separate website, and so there will be no shared or additional value from the blog with the site. This is also why putting your blog on an entirely different domain isn’t a great idea. There is an argument for subdomain blogs, such as they can comfortably espouse different topics to your main site, or that they get round any tech or implementation issues.

I think that point of view is pretty misleading, here’s why. If you are blogging to add relevant content to your site then why on earth would you want it sat elsewhere? Also why would you want to write posts about off-topic stuff? If SEO is about nurturing a theme and related topics that draw attention to your site, and allow for increased site linking then don’t do it on a subdomain.

The argument that it deals with integration issues is also pretty lame. If your site cannot comfortably run a blog and it needs one then think about changing your site. This isn’t a throwaway bit of advice either, it’s simply the right thing to do. On the flipside, you could always review why you want a blog.

Here’s some reasons For and Against having and running a blog:

For: A blog can…
…give you the opportunity to express personal views
…allow your site to have a different, less corporate tone of voice
…help you create a dialogue with people
…get you valuable feedback
…grow your networks
…spark ideas
…make you a better writer
…ask for help
…tease you out of your comfort zone
…promote main site pages
…get you noticed amongst your peers
…spread ideas
…boost the authority of your site
…regularly add content
…promote the main theme of your site
…allow you to help people
…give you insights into your audience’s behaviour and reasoning
…provide a voice for otherwise “silent” stakeholders

Against: …
…hmm, nope, can’t think of one reason not to run a blog.