I also like Giant bikes for their great value and good specs. That company's Cypress LX bike ($470, but maybe you can find one on sale; www.giant-bicycle.com) has an aluminum frame, Shimano components, and a nicely upright position. Amazingly, it also has disc brakes, and in a nice touch, the tubes come pre-treated with Slime anti-flat goo. The Cypress also is available in a women's style, so you can try both the men's and women's and see what you prefer. The Cypress will be a bit lighter than the Smoke, but even with its shock-absorbing seatpost, it's still going to have a slightly stiffer ride.
Lastly, take a look at the Jamis Aragon ($400; www.jamisbikes.com). It too is an aluminum bike with a suspension seatpost, which helps burr the edges off what otherwise would be a moderately stiff ride. It's nice and upright, plus has a 24-speed drivetrain (as do the other two) and a mix of reliable Shimano parts.
Most bike shops are happy to let you take a bike and ride around for a bit, so I highly recommend you ride three or four bikes, thinking about how the bike feels on the road, what seems to "fit," and just how the whole thing sings to you. I'm sure you'll find one that hits the right notes.
Looking for a reason to ride? Look no further than Outside Online's 2005 Tour de France coverage, including daily news reports, behind-the-scenes journals from Lance Armstrong's coach, and exclusive photo galleries.