Sigh... Nope, I didn't get to go out there afterall.
They called back on Friday and said they didn't have time for the onsite visit this week or next. They say they're still very interested in talking to me, but "the timing isn't right". They say they'll call back in a while to reschedule. No word on how long "a while" will be. They also said they want me to call them back if I get another offer from another company, they'd say they would want the chance to make a counter offer.
All in all they really do sound like they're interested in me, but I can't help feeling that they just blew me off. Time will tell...