And about that dark "rectangle" on Opportunity's way to Vostok Crater
Squyres says they have no plans to investigate it, even though its dimensions do
measure 1 by 4 by 9 (just kidding about the dimensions part).
I don't know - with Opportunity's luck, I personally would not let it pass by ANYTHING
that looks even remotely interesting on Meridiani Planum - would you?
By the way, they are considering MP as a landing site for the MSL, as it is considered
a good place for preserving fossil microbes, especially around Endurance Crater.