If you are launching a site and want to try as you will see a new theme, or as will be CSS changes you are doing, or just present a sketch of a site for a client, often the most tedious is to start creating content shows that "fill" the site and can appreciate what it can offer.
Well, in case you did not know, is an XML file in the repository you can use WordPress for this utility . Find it at: http://svn.automattic.com/wpcom-themes/demo/demo-data.09-27-2010.xml
The downloads on your computer, go to sample site and in ' Tools -> Import 'choose' WordPress '. If the importer is not installed install it (remember that now is a plugin disabled by default) and you can import the xml file you just downloaded.
What you get is a content site where you can plump will show as ordered and unordered lists, the h1, h2, h3, bold, italics, images on one side and other stuff. Very useful is not it?