Welcome to Free Republic - your home page is well-written and very clear! I wish I could go over to DU and engage in the kind of discourse you will be embarking on. That's the difference between the two sites - you are correct that FR's been trolled to saturations, so I hope you excuse the wariness. :-)
Gospel truth: never been to DU. I had to ask a FReeper what "DU" stood for. I'm an active and partisan Democrat, and had never heard it mentioned. Surprising, actually. I usually hear about stuff like that.
I imagine curiosity will get the best of me eventually and I'll look it up. I've been told that they have been known to post pornography on their site(??). If so, it would not be my cup of tea, by a long shot.
It looks to me like FR has an incredible auto-immune response to trolling, so I wonder why they bother.