I just got in to U Penn, and since it's so late in the game, I'm not going to get a chance to visit and see things for myself. I'm already going about contacting Profs and grad students, but I'm interested in anything that people here have to add. No one is listed in "Fall 2008 Open House Information" as having visited their open house, but that doesn't mean that you aren't out there. The thing I'm most curious about it the "department vibe" (are the grad students happy/paid enough to live, do they get screwed by quals, etc.) because that's hard to detect without a visit (even then, it may be hard to detect).
Beyond that, I'd be interested to hear any thoughts about their (hard) condensed matter experiment folks. Charlie Johnson gave a colloquium here, and I thought it was interesting stuff. I've looked at what other people there are doing, and I find most of it interesting, even if it's not exactly what I'm thinking about doing (which is more quantum computing oriented).
I'm already familiar with the area (West Philly), so that's not something I need information about.
Oh yeah, since these type of posts require a face off between two schools, comparisons to Wisc is fair game too. My guess is that I'll end up sticking with Wisc, in no small part because I really liked what I saw on the visiting weekend, and I doubt that I'll get a good enough feel for Penn in the next few days -- better to play it safe and go with what you know.