To change the tranny fluid..?
 

So, as I have completed servicing the major items on my new car to-do list I turn my attention to the transmission. It seems to shift fine, on slow acceleration it seems the 2nd to 3rd shift seems kinda slow to engage, but besides that it has been working like a charm. I heard from a co-worker that is currently attending college fixing cars tell me that if the transmission shifts fine, dont bother changing the fluid, especially if you know it hasnt been changed in forever..

Is that true? I kind of always thought it should always be changed.. apparently the argument is the gunk in the tranny will get loose and travel around in it. Any opinions would be great, thanks!