Chances are if you are reading this blog, you either have a blog for your business or you're thinking about doing one. It's a very hot topic these days and one we avidly follow at BlueTie as we blog here. Getting started with a blog is easy- we use Typepad as our blogging platform and they make it very easy to get set up and start blogging.
Once you've got a blog you're faced with every blogger's dilemma: How do I get people to read this thing? Start by checking out Guy Kawasaki's great post on ten ways to drive traffic to your blog (and read him regularly for a lot of seriously useful business advice).
The keys to blog popularity: Content, content, content, linking. You need to post frequently, at least 3 times per week. Every blog on the Technorati Top 100 has at least 700 postings so volume is important. Next, blog about things your customers are interested in and provide as much value as possible. Help them be more successful and they'll stay loyal. Share your secrets and business intelligence.
Linking. Technorati measures popularity by how many links you have to your site from other relevant sites and how many outgoing links you have to other relevant sites. Note the italics on the word relevant- tons of random links from unrelated sites aren't going to help your search rankings.
Blogging is habit-forming, especially when you start to get interesting comments and links into your site. It's an organic way to connect your business with a community of interest which is always a good business model.
Update: Here's a completely different but very interesting view on what does and doesn't work in blogging from engtech.