Write quality content
It might sound obvious to most of us that your blog’s content has to be excellent. In many cases, however, bloggers write mediocre posts and spend most of their time trying to drive traffic to their blogs. Granted, they get a fair amount of visits, but those people will never come back. Converting one-time visitors into subscribers is by far the most important thing you need to do to keep a steady flow of traffic visiting your blog.
There is another excellent reason to write quality articles. The better your content is the more people will link to your blog. And as we all know, quality incoming links are the key to high search engine rankings.
Let your readers subscribe
There are two major ways people can subscribe to your blog: email and RSS. Give them both options. RSS is a great technology but a huge percentage of your readers are not very familiar with it.
Submit your feeds
Every time you write a new post, submit its RSS/Atom feed to the major feed directories: FeedAge, FeedRaider, FeedAgg, FeedFury, GoldenFeed, and BlogDigger. Also submit your blog’s main RSS if you haven’t done so yet.
Ping your posts
When you ping your posts, the search engines are more likely to index them faster. These are the ping services such as pingomatic.com and feedburner.com
Social bookmark your own posts
Create an account with the top social bookmarking services and bookmark each new post that you write. These are some of the ones I use: Digg, Delicious, Propeller, Technorati, Reddit, Google Bookmarks, Yahoo Bookmarks, MSN Bookmarks, Blinklist, Linkagogo, Wists, Kaboodle, Furl, Faves, and StumbleUpon.
Add social bookmarking capabilities to your blog
Give people the opportunity to bookmark your posts. There are several plugins that work for most blogging platforms. My favorites are ShareThis and Sociable.
Forums and blogs
Interact with your community, provide useful tips, and answer their questions. Become an authority in the field and invite them to visit your blog. Don’t spam them, though. Make sure that you are helping them, not just posting your blog’s link everywhere.
Use viral marketing
I think that all blogs should have an option to “Tell your friends” about it. Sure, your visitors can copy your link, open their email clients, and send your blog’s link to their friends. But if you don’t make it easy for them, chances are that they won’t.
Dr. Scott's Business Blog 
Good post! Anyway, you also could use this 150+ social bookmarking to promote your site!