#3 - May 28, 2010, 2 p.m.
We are unable to identify exactly how a player's account is compromised, Laki. Accordingly, we cannot say for certain that downloading the program you're speaking of is responsible for compromising a player's security. What I can tell you is that we have received many reports that there are impostors out there disguising themselves as commonly downloaded (and likely safe) wow-related programs, so be sure that the website and download are legitimate before installing.
If you have any specific questions regarding the overall safety of these programs, I encourage you to post on the UI & Macros forum where many addon developers regularly post. Seeing as they have more first hand knowledge of addons, they may be able to help clarify why there are security concerns.
Also, be sure to review our support article dedicated to account and computer security:
Account and Computer Security:
http://us.blizzard.com/support/article/30794