Using Tor isn't a crime, but the NSA targets people who use or even search about Tor or VPN services for collection through the XKEYSCORE program. So his post is exactly right - using Tor does "put you on a list", but that alone isn't sufficient to be arrested. The NSA documents further state that Tor is relatively difficult to attack and the best they can do is deanonymize a small (and importantly, random) fraction of users some of the time.

http://www.wired.co.uk/news/archive/2014-07/04/nsa-targeting...