Allow me to enlighten you on what I know here....

While ice might be found on Mercury, the Chances are slim to nonexistent. It'd have to be somewhere near the pols, and with the way that planet shifts orbit, those safe spots would be gone fast. It barely rotates, but it still does. Still should be interesting to find out what caused that feedback on the probe.

As for NASA overblowing things, they do that. But we did find out plenty about the moon from our trips there, though we weren't too interested in that part at the time (Cold War = world's biggest piss-off).

And as for Mercurian temperatures, it's actually just above absolute zero on the dark side, which is easy to maintain due to it's slow rotation (For a while people thought it was tidally locked). I suspect that it would remain cool until you hit it's newly-discovered liquid core (or mantle. Whatever they want to call it).

If people did want to mine Mercury (which I'm all for), then we'd most likely establish colonies there. No point living on another planet if you couldn't do it in comfort.