On 24th / 25th of february, a ‘social worm’ attacked a lot of gmail users. You can see TechBuzz mention about the viddyo Instant messaging worm here :
Viddyho.com is spamming every one beware !
However, I noticed that viddyho was still being discussed on twitter even though the viddyho site was tracked and banned on the very same day.
Again, I’d like to mention that viddyho is not a malware, but it was an Instant Messaging worm. It doesn’t seem to have created any noticable problems, yet !