A case could be made that blogs and blog hosting websites like WordPress and Blogger are, so far, the most important innovation of this century, technological or otherwise. Prior to the advent of blogs, publishing online was a task reserved for the computer savvy. Sure, sites like Geocities and Tripod lowered the barrier, but still required a good deal of work and at least a passing familiarity with HTML. It wasn't until blogs that the average person - my mom, my grandfather, etc. - could, with a few points and clicks of the mouse, get their thoughts, feelings, and information out to an audience of, potentially, billions. In mathematics there is the concept of different cardinalities of infinity. While both the set of integers and the set of real numbers are inifinite sets, there are 'more' items in the set of real numbers. It's a 'bigger' infinity, if you will. In a similar vein, both e-mail and blogs shrink the world and allow people who may be vast distances apart to communicate with one another instantly, but blogs go a step beyond e-mail (or the telephone or fax machines) in that it allows for one-to-many communications. With an e-mail message you can send urban legends and corny jokes to your aunt in Baltimore, but with your blog you can share them with the world at large.
Blogs have had a very profound affect on society as a whole. They have democratized the publishing process and made the idea of citizen journalism a reality and, in doing so, they have quickly neutered industries that were flourishing a mere 10 years ago. Why buy a newspaper when you can get your information online? Why pick up a copy of Sports Illustrated when you can read more interesting and in-depth articles written by ex-GMs, current athelets, and impassioned fans? And what's the motivation to purchase a programming book when there are countless developers sharing their tips and tricks, what works and what doesn't, on their blogs each day? Of course, there are benefits to be had by big box newspaper and magazines and having content presented on pieces of paper. Print media is not dead, but it has been relegated to a niche market, and blogs are a big reason why.
Blogs have also had a profound impact on the Web 2.0 landscape, namely in the areana of syndication. Ten years ago content syndication was in its infancy. Blogs were the first application that used syndication - Dave Winer invented RSS in 1997 to syndicate content from his blog, Scripting News. As the popularity of blogging grew, the RSS standard matured, the Atom standard was created, and non-blog sites started embracing syndication. Today, virtually every website that produces content on a regular or semi-regular schedule provides a syndication feed. We have blogs to thank for that development.
It may seem like an over-exaggeration to say that blogs have had such a profound impact, but consider this - how do you think my daughter will react when I tell her, 15 years hence, that there was a time in my life when only people who were 'computer experts' could publish content online. I think she'll be flabbergasted, and I think that surprise and disbelief she'll have is a testament to how important an innovation blogging has been.