Plus, although I don't have personal experience but I have heard many a woman claim the uncircumcised can be a little smelly down there. Why decrease the chances of a future healthy well rounded (BJs) sex life for your son?
Dicks can get smelly whether they're circumcised or not. As Lindsey says, it really comes down to whether you wash it.
As for better sex, uncircumcised dicks have a couple of things to their advantage-- that little bit of skin makes it easier to give a blowjob (and hence probably the blowjobs are better, but of course I couldn't say for sure) as well as making insertion smoother.
Any woman who would refuse to have sex with someone who is not circumcised is, frankly, not a woman he should want to have sex with anyway.