Most people who use Citrix because of the Rush ads aren’t using the products you’re talkiing about. They’re using GoToMyPC for remote PC access, with a few using GoToMeeting for conferencing. Citrix doesn’t advertise XenApp on Rush Limbaugh :P
I don't remember any ads like that on rush but I tend to tune out ads if at all possible.
Maybe they can make up the difference by buying ad time on Current TV. I'm sure their viewership is in the tens of tens.