I have been to the Open House for the past 3 years and the schedule is pretty much the same, so looking at the 2008 schedule will give you a good idea of what will be happening on the 4th. I remember going with a few classmates who were accepted and had separate activities, but I was very much focused on the prospective student information sessions and don't really remember what they did 🙂
There is a Facebook group "VMRCVM 2013" that has some more information that some current students have posted, including things that happened on the day BEFORE the actual Open House, like "Pie with Professors" and actually sitting in on classes. So maybe (hopefully!) more information will be sent out to accepted students about these things.
Apparently there will also be an information session on housing, which I hear will be at a premium this coming year in Blacksburg. Apparently only 75% of the undergraduates at Va Tech can be housed on campus next year. While I was at my interview, my mother and I looked at one apartment complex that was already completely booked for the next year! And of course, the name of the apartment complex escapes me right now... *sigh* So anyway, an info session on housing would be MOST welcome imo 😀