Goodwill with hiring managers is good. But in a down economy it'd be helpful to boost your reputation more broadly.

If I were running your college's program, I would invest in a presence at Defcon. If just one your students could use their skills to uncover and present something genuinely interesting, it would be worth covering their airfare and accommodations just to get your logo on the screen. If you could do this every other year, your program would have an unparalleled brand.