Basically,
For those with display enclosures, its not exactly aesthetically appealing.
For those with a fair bit of cage furniture, its a pain to take everything out once or twice a week as spot cleaning is impossible, you have to replace a whole big sheet, which means taking everything out.
For those with crazy balls that just hate paper and shove it aside, or love it so much and always get under it, it could be a problem. All the mess the ball makes wouldn't be on the paper, it'll be on the enclosure floor, and pythons under a sheet of paper which has a water dish sitting on top.. They're just waiting to lift and spill it. Happened many times with me even though I have an amazingly heavy one.
For those with really bad humidity problems, it can't be misted and retain moisture/humidity at all.
These were pretty much all the problems I faced which forced me to switch to aspen. I agree newspaper's great, but sometimes can be a little of a hassle.