That's right, Samir, these were just
$45 for Black Friday—quite a deal! When I saw that, I actually emailed Best Buy to ask them if the particular boards they were selling had blue or brown switches. But it took their offshore support staff 3 days to answer me—to tell me that they didn't know, and that I should "call Logitech"—and by then the sale was over.
I later learned the earlier G710+'s were the ones with browns. (This doesn't explain why Logitech released the G710+ first and
then the G710.)
Since I posted here, I've read complaints about the stems breaking on the Ctrl keys on these. There's a
thread about it here on Logitech's support site.
I suspect this is happening to gamers who are mashing their keys and, in their haste, hitting Ctrl at an angle. And Logitech's being very good about sending out replacements. However, if I got one of these and expected to give it some serious use, I think I'd be proactive and reinforce the Ctrl stems—e.g. by using a bit of JB-Weld or 2-part epoxy to glue a few loops of thin, uninsulated wire around them, lightly sanding them first to improve adhesion.