I wonder how much data costs per kilobyte from Mars?
Or more accurately: The fixed cost for getting the dataline installed is extremely high, but once it's there and has no other use than sending data back to earth it's almost free to use. The only cost is the electricity used, and since it's on a nuclear battery that will run for many years you can discount that.
In other words: Send as much data back as you possibly can. Prioritise it and send the most important first of course, but don't ever let the line sit idle.
Most of the time the link is going to sit idle; an orbiter is only overhead a few times a day, a few minutes at a time. So there will be scheduled bursts of communications. AFAIK the Curiosity-orbiter bandwidth is about 2Mb/s, and the highest-speed orbiter-Earth link is up to 6Mb/s (that of Mars Reconnaissance Orbiter--MRO has returned more data than all other Mars missions combined.)
Curiosity also has two antennae that allow direct communication with the Earth (when it's over the horizon) but they are too slow (hundreds of bits per second) for heavy-duty image downlinking.
It would have been a reasonably good Internet connection if not terrible ping of 1680000 ms (almost half hour).
And assuming you were talking about the market price of using the channel for just anything, add some valuation of the opportunity costs of not using the line for the things NASA will use it for.
edit: why bother saying this? Private industry is entering space, professionals who know something (unlike me) will be very interested in figuring out the value of things NASA has been doing.
Pretty sweet! It can run for a minimum of 14 years. I don't recall the last rovers using nuclear?
The situation might change enough being on planet where the sun is slightly filtered by the thin atmosphere, and the sun doesn't shine ~12 hours a day.
RTGs have many other advantages: they provide heat as well as power (which is really important on Mars) and they don't wear out when covered with dust. If Curiosity stops running within a decade, it won't be because of power.
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