I'm sorry, but if it is dishonest of Canon not to advise people of the faults, it is even more dishonest of this site not to release the info.
I understand this site is here as a business, and to make money, but to play the game of "Should I tell you what I know" sounds like you are waiting for a payoff not to release the info. Whether it is money, equipment, or a sudden better relationship with the company, it looks like you want a hand out.
Regarding the legalities, if you had released the information and clearly stated you had been sent it and were passing it along WITHOUT verifying it as fact or not, and listed it as possible rumor, it would have been fine.
To say I'm disappointed in this site is an understatement, and I would guess the person who sent the info is as well. Canonrumors just lost a lot of credibility.