They entered private beta in April 2004 and didn't hit the mainstream until February 2007.
There are still 25M accounts in the My Space data so the incident certainly happened that early 2007 time frame (I recall there were a lot of people in the beta, but I doubt it was enough for 25M of them to have My Space accounts), but how much after?

My Space was also a haven for middle-class suburban emo teenagers to whine and moan about how their lives are so "tough", even though they probably never got one in the face.
A typical person's Myspace page was saturated with annoying music, anime and "artistic" pictures, and the use of many quotes. Many trolling groups, such as Penis Pump, defaced My Space pages for the lulz.
Unfortunately, the game grew immensely too popular and resulted in IRL drama and became the leading cause in at least 100 IRL suicides.
The My Space game had announced that the game would not be over until every teenager had become an hero.
The group decided to mimic the more popular features of the website.
Within 10 days, the first version of Myspace was ready for launch, implemented using Cold Fusion.
My Space was the cancer that brought us Boyce Avenue, a self-centered, untalented piece of whiny shit.
Originally, My Space was created as a game to see who could get the most friends online.
The magic forest in Japan :-) Bamboo trees are a favorite, add a path through the bamboo and I'm double happy.