Also Emily Lakdawalla wrote up a nice article on the wheels for the Planetary Society:
http://www.planetary.org/blogs/emily-lakdawalla/2014/0819063...
http://www.planetary.org/blogs/emily-lakdawalla/2014/0819063...
Surprised it lasted this long. I understand weight was a concern, but surely for $2B, there's some exotic, more resilient alloy that could've been used? Or maybe just make those middle wheels 1mm thicker and eat the extra 3 1/3Kg.