I don't know. I haven't done any studies, and I don't know much about the topic.
But I can't help but identify Cho Seung-Hui with Wayne Lo, the killer who rampaged across my college campus (Simon's Rock College of Bard) in 1992 and left two dead, two permanently disabled, and a number of others wounded.
Both are first generation Asian immigrants (Lo is Chinese), coming to the US at a young age. Both, while in college, fell into some sort of depression, began espousing and glorifying violence, and committed violence in the months leading up to their respective shootings. Both were outsiders at their schools, and loners in general. In Wayne's case, his writings before the shootings and his statements afterward indicated that he wanted to rid the campus of sin, homosexuals and drug-users. Cho, similarly, railed against "rich kids", "debauchery" and "deceitful charlatans" on campus.
There are other things that probably are incidental but I can't help but notice: both seemed to be fans of guns, both played basketball, both were loners.
Of course, by pointing out their Asian heritage, to some people I might be running the risk of crossing the line into racism. For example, see Yen, Rhoda J., Racial Stereotyping of Asians and Asian Americans and Its Effect on Criminal Justice: A Reflection on the Wayne Lo Case, 7 Asian L.J. 1 (2000). Ms. Yen makes the argument that Lo's Asian heritage was something that may have predjudiced the criminal justice system against him. While I understand Ms. Yen's argument that perhaps the prosecutor or the investigators may have used racial sterotypes in their building of a case, I find it difficult to see how that may have materially affected the outcome, in that there was no question of fact as to whether Lo did actually go on a killing spree.
Either way, it is not my intent to say that these killers are who they are because of their race... I would no more argue that their rampages were caused by their race than it was by their shared enjoyment of basketball. However it is still interesting to me that they are Asian, which seems to be a significant exception to the general rule that mass killings are carried out by white males (there have also been a few others, for example Gang Lu in Iowa). Across the board, college shooters seem to be males under some pressure for success (academic and/or sexual), which would seem to include many Asian males (Which is, of course, the Model Student stereotype that Yen argues against). Having known Wayne and seen what led up to the murders, the VT case jumps out at me because of the similarities. Lo was very smart (as was everyone at Simon's Rock, a college that took students after their sophmore year of hich school), as well as a brilliant violinist who was under a lot of pressure from his parents to succeed. I am curious to see if Cho was under similar pressures to Lo as we learn more about him.
A large dissimilarity between Cho and other cases is that he killed himself. Most mass shooters, like Lo, want to read their headlines in the morning and as a result do not kill themselves. Cho bucks that trend.
I have no real thesis here... simply working through my thoughts after learning of this horrible tragedy. Years ago I might have been seriously affected by a shooting like this. I am, in a way, heartened that after 15 years since Simon's Rock I am able to both recognize that a tragedy occured in Virginia and feel for the school, the students, and the families and friends of the deceased, and at the same time can somewhat put it in perspective. Thirty-three is, after all, less than the daily death toll in Iraq. But if one of those thirty-three is your loved one, that perspective will never fully be there. While the time is long past where I couldn't get through a day without thinking of Galen. I still miss him greatly, and more so when an event like this triggers memories of what he went through. Everyone at VT is in my heart and thoughts, and deep condolences for their loss.