I see a few threads here about people thinking about getting a D5000, I would say go for it. Adorama's deal for it with a 18-55mm VR lens for $525.00 and free shipping made the decision to go this route over a D3000 easy for me. It's a refurbished by nikon package, but I've always had good luck with refurbished. In my experience refurbished from a manufacture, like Nikon, means like new with better inspection procedures to make sure everything is what it should be. Less likely to get a lemo
I don't remember all the differences between the two, but I really like flipping the LCD so it isn't visible for a few reasons. First, to protect the LCD. Second, to hide it from my 19 month old daughter. She always wants to see the pictures as soon as she notices a camera. With the screen flipped away, she thinks this camera doesn't have one, so I get shots I couldn't before. I also like hiding it on myself. I use it as a way of stopping myself from chimping after every shot. I actually annoy myself doing it. All I have to do once the camera is set up is make an adjustment using the info in the view finder, or pull the screen back quick to take a peak at the info. (One reason I like the hinge at the bottom instead of the side)
Above all this sensor is great in low light (in regaurds to my personal expectations). I wanted to go with this or a D40 for shooting natural light. From looking at reviews and photos I figured either would do nicely up to ISO 1600. What really impressed me with the D5000 is most of my pics at home of my daughter, no flash and ISO on Auto, are at 3200. They look great!