Blog features and how to use them for marketing

One of the things I enjoyed about the blogging experience was learning to use the "gadgets".  Setting up the blog is similar to building a website, the difference being that you can easily change the features at any time and with a website I find that more time consuming.  Features of blogs allow you to personalize your space with ready made templates, or if your savvy enough you can create your own.  You can add links, videos, information about your geographical region, etc.  You can personalize it with your own pictures or, as in the case with 21publish, you can let your community members personalize their own spaces. 
As far as marketing the blog, I personally would only be marketing to my own students or through another community.  The only other reason I might use a blog would be to write about cooking or horse training, my other passions.  I don't see for me personally a use outside of my own interests since I'm not attemping to market a product.  So to market my blog I would be utilizing information that was considered private so my classroom students and their parents would receive an invitation to join my blog, which would end once their student had fulfilled the class requirements.  As far as management for this type of blog, purging the site, once you had a class turnover would minimize excessive clutter.