While I agree with you that no press is bad press, in the Internet realm you also have to be aware of keywords. HN comments right now are littered with none-to-flattering words for Joyent, which then get indexed by Bing/Google and can hurt the reputation for Joyent.
Worse yet, Joyent's PR may backfire and make them look like naive idiots for making claims they can't back up...especially when it comes to throwing rocks at the Amazon juggernaut.
This says it all really, just a bit of PR to boost awareness of their product...and the HN community has taken the bait.