I just want to say how much I appreciate WPMU and it's developers. Kudos for really good stuff!!
I have recently been having a blast playing around with the Nelo theme. For each use, I create a unique child theme for it that allows me great versatility with changing/editing/adding templates. One client in particular likes the theme so much she is using it on two of her sites!
To see how it's playing out (and bear in mind that I am still tweaking a couple of them), check out these sites: