I have the Schwinn IC Elite and really like it. The deciding factor for me in choosing this bike was that I could have it set up and delivered, or else I would have considered a less expensive bike. Here are some things to look for:
Sturdiness
Belt driven vs. chain driven (I think the belt might be quieter and easier to maintain but not necessarily a superior option)
Adjustibility of seat and handlebars
Handlebar configuration/shape and thickness
Flywheel weight
Cup holders (wouldn't have considered this, but my bike has two and I use them both)
Stopping mechanism - The IC Elite stops just by pushing back on the pedals
Warranty and service
When I researched bikes in January, I found that almost everyone was happy with the bike they had chosen from the economical ENC 200 to the most expensive Revmaster, so hopefully you can't go too wrong