I've been looking at the CSS grid layouts like the google blueprint example. http://code.google.com/p/blueprintcss/ I think they are a great way to go for general page layout and wondered if any of the open source CMS packages can integrate this type of layout.
I was looking into this recently for a future site. I'm going to use Drupal - they have an extension here called Advanced Theme Construction that can build a theme for grids. I haven't used it so can't provide any feedback, although Drupal is a very good quality CMS so I would imagine that, with a some attention, it works fine...