Yeah, it's not common on my campus either, but it also depends on the chapter.
My chapter got 50 new guys this past school year (07-08) and this is the majority of our chapter.
A lot of the older leadership has/will graduate, so its up to us guys that were rushed in 2007 (Spring 08 and down, not so much) to step up to leadership positions. I was the first from the fall pledge class to be appointed to e-board when someone resigned and I'm running for a higher position this fall.
But president... thats another story.