I'm cut and I like it that way. I don't wish I was uncut.
REASONS:
It might be less sensitive (with a condom on in particular) but that is not such a bad thing when you can fuck harder and longer hehe. The intensity of the pleasure is the same I believe, just takes more friction to reach the same level of stimulation.
The cleanliness issues, no dick cheese issues - blowjobs are more pleasant for the giver, no smeg flavour issues. No infections of the foreskin.
STDs - very significantly reduced risk of transmission
Yea that's about it. Oh and I had this friend who is uncut (claims 7.5") and he was telling me that when he fucks hard his foreskin starts to become painful and apparently it tears and sometimes it will bleed. So there's another potential downside to the ol foreskin, and that would be particularly bad in terms of STD transmission.