Never trust a link that's sent to you randomly from people you don't know/remember. Also look at the URL carefully. An example is the fact that the URL has '.com-tp.eu' in it isn't a normal type of link (that's from the dozens of tells I got from that kind of raffle thing)

I kept a list of the people that sent me those tells, and all of them have been people with multiple level 80's on their characters. I feel bad that it happened to them, so at the very least I check if they're still in an FC and contact their FC members to spread the word about it. But a lot of the times people are too trusting with random things sent to them in tell, so be sure to spread the word at the very least and tell people to change their password right away if they have gone to any of those links.

What's worse is that kind of phishing scam was going around like a plague during the Make it Rain Campaign. When I was posting shouts about it in popular areas as well as making party finders to spread the word, 90% of the time I got people just trying to joke around about it. There's a time and place for joking, but informing people about a scam isn't one of those times.