Mine is messy. I'm not proud of it but I have the smallest room and barely any storage space so everything seems to be on top of each other. Part of the reason I'm going to halls next year (hopefully for free!) so I can keep it tidy and organised. Seriously regretting getting the small room!
I brought an awful lot of stuff to university, so my room is pretty full and very tightly packed [I've got everything from printers to clothes racks and even a portable tightrope ]. However, it is also tidy (as it is always) - not just out of necessity because of the amount of stuff I have, but also because I hate disorder so it'd be tidy anyway. The only time I consider it "untidy" is when I'm working late into the night and have thousands of pieces of scrap paper floating around containing various mathematical jottings, ideas, and rough working. That's my maximum level of mess & I always tidy up before going to bed.
Mine's tidy, but that's purely because I have a veeeery small room. I physically can't leave things lying around if I want to be able to open the door (it only opens halfway as it is, due to the chest of drawers blocking it). It also means I only brought a very small amount of belongings with me (I'm a 4th year now, I've become pretty efficient at packing the bare minimum..).
I will, however, admit to having the typical hoard of plates and cutlery stashed in various places. (Reusing the same plate is easier than washing everything up.)
I spend 20 minutes cleaning my carpet everyday. I also change my sheets every two weeks. My books are chronologically organised according to subject. I vacuum every other day as I can't stand a dusty floor.