This can only mean that they have already broken the Skype encryption - and want their opponents to use it.
Are you sure that the best way to hide the fact that you have found an attack against Skype is to advertise a contest with a billion dollar reward to anybody who can find the same attack (or any other one)?
Can you think of a better way?
Maybe not talk about Skype attacks at all. You know, keep it a secret.
We aren't dealing with a police agency, remember. We are dealing with a "national security" agency, and that phrase is an umbrella term that covers every type of shady business governments have engaged in since time immemorial. The NSA does not deal in "evidence" and "courts." It deals in "should we sic CIA assassins on this leader?" and "should we orchestrate a smear campaign against these nearly successful activists?" and other fun questions.
I vaguely remember reading something about the skype team saying they would "cooperate" with law enforcement officials, but I'm not sure if that meant actually listening in on encrypted conversations or just sharing the IPs and time of connections to servers.
This reads as FUD they made up to sell ad views.
If somebody who is reverse engineering Skype found it, and it would eventually be found, the company would be ruined.
Even if skype came out and said they were recording every conversation, I don't know if all that many people would stop using it. There wasn't all that much outrage over immunity for the big telcos, for instance.
Or did you mean the company would be ruined for some other reason besides loss of reputation? Maybe I misunderstood the comment.
It's more intentionally malicious to distribute software with a backdoor than to do what AT&T did so I really think it would upset people more.
Remember the Sony 'rootkit' fiasco? And that wasn't even really harmful, just annoying.
I'm absolutely positive, no doubts whatsoever, totally sure that it means that they can't but by saying that they can't they're trying to get you to think that they can and want their opponents to use something else.
My reasoning is iron-clad.