I found this fascinating quote today:
One of the great things about the web today is that you can choose from hundreds of services that will host your blogs, lifestreams, photos, videos, and music. One disadvantage of this, however, is that you typically have very little control over the actual experience. You can’t, for example, make changes to themes on WordPress.com or customize the way your pictures are shown on Flickr. However, thanks to a large number of open source projects, you could do all of this if you hosted your own blog, photo gallery, or mixtape service. In this post, we will show you how to do that and which services we like to run on our own domains.readwriteweb, ReadWriteWeb, Jan 2009
You should read the whole article.