It is amazing how powerful a blog can be. Not only for SEO; yes it can help you gain rankings if used correctly; it can also get your point across and cause change.
The WTF SEO Blog has been going for a few months now; albeit left for long periods of time while I was helping out a client who had every conceivable Google penalty under the Sun. Not my doing, mind and now corrected!
The Power of Blogging; every SEO should have one!