For me: "that person owns no real dress pants"--particularly when it's on "young" people (that 18-34 demographic, I guess).
I can see how some of the earlier posted pics work as conscious attempts to integrate formal and informal elements. But I'm not a fan of how jeans, a tie, and a sweater counts for formal for many young people mainly because that's all they have in their closet.
I would have agreed that jeans and running shoes is "bad" until I had to go to physical therapy for ankle problems and needed shoes that were comfortable to walk around in. I remember reading on blogs and such that the right, well-fitted, usually expensive dress shoe can be just as comfortable as sneakers. I've never found that to be true and still don't buy it.
I just thought running shoes looked fine with jeans. In college plenty of guys did that, but then I guess most people here would think we all had bad taste. Cambel, have you tried wearing cole haan shoes? I read they are formal shoes that are made by nike with a nike air sole for comfort.