Wilco rules and I'm a big Uncle Tupelo fan, but I can't write off Jay Farrar. I have all 3 Son Volt albums, and I think they're great albums. The Mermaid Avenue albums are excellent. Jay Bennett is a freakin bozo, but damn he is a great musician and an awesome songwriter.
I need to check out Son Volt more. I don't like Farrar's stuff on the "March 16-20 1992" Tupelo album because it sounds too preachy in a "social justice" sort of way, as though he thinks its 1933 and he's got to save the coalminers from the evil capitalists.