Not really
Even if they already knew about it, Meltdown and Spectre are nearly useless to the TLAs for any Windows, Linux or OS X system - because they already have a pile of 0 days for those which are far worse. The noteworthy thing about Meltdown and Spectre is that is a hardware level bug, so it would work on ANY operating system - so if they had a target running some adversary's formally verified OS that was otherwise hack-proof, they might be able use this hardware flaw to gain access.
Biting the hand that feeds IT
