It depends on specifically how you want to use the bike. I review several types of bikes on my blog: http://www.cyclingforbeginners.com
If it is mainly for transportation, errands, etc., around town, I like the Electra Townie 7D.
If you want to go faster and longer -- group road rides, races, etc., the Giant Defy 3 and the Fuji Newest 3.0 are both really good values.
If you want a fast bike with lots of gears, but not the bent over position of a traditional road bike, I'd look at a flat bar road bike like the Cannondale Quick 4.
For more commuter-type bike suggestions, please see my hub: http://hubpages.com/sports/Best-Commuter-Bikes
Hope this helps!