I came in to say the exact same thing. Hey, san! It is not worth it irritating me, to for a small chance that I sign up. Plus I the people whose IMs I got the msg/spam from were not aware that I would be getting a msg from their IM. You might have said that in small print, but it is definately shady.
"This messages are because of vulnerability in Heysan.com.
Once you click on any of this messages your buddy list will also start receiving the similar messages."
"This is a virus link. Your Gmail account has been infected. You need to clean out your computer with antivirus and antispyware scanners." "Yeah, it sure is a virus and is spreading quite alarmingly. Be cautious where you enter your passwords."