@disc440, I'm looking at cwpcblog.wordpress.com side-by-side in Safari and Firefox and see no difference, and when I compare it generally to the demo site here, I'm seeing everything in place.
The sunspot theme is a left aligned theme, and if your browser window is set wider than the theme, you will see a large empty space to the right. You are not using the same theme, so that is not a valid comparison. Your theme has the main container for all the page content centered. That is why yours doesn't have the large blank area to the right. The blank area ends up being split equally on the left and right on your site.
Each theme designer decides how they are going to layout and present their theme and in the case of Sunspot, the designer decided to float the main container to the left instead of centering it.