NASA announced the results of a contest to name the Mars Science Laboratory rover - its name will be Curiosity. Clara Ma, a sixth grade student in Kansas, submitted the winning entry (you can read her brief essay explaining why she chose this name).
I think it's a good name, and a nice progression from Soujourner, Spirit, and Opportunity. When I was at the JPL Open House a few weeks back, I saw Curiosity in pieces in the assembly clean room, and I took pictures of the two development models that were on display in the Mars area where I was talking with visitors about the "old" Mars rovers Spirit and Opportunity. Unfortunately none of my pictures came out all that great, so here I've used a JPL artist's rendering, which shows the relative size of Spirit (or Opportunity) vs. Curiosity. No human scale there, but it's basically the size of a car - something like a Jeep or a small SUV, while the MER rovers are something like golf-cart size.