Nikon D5000? Is it a good camera?

I just found out that I'm getting the D5000 for my birthday. I'm a photographer for my school's yearbook, so I'm used to using D70s, D80s, and D90s for my photo assignments. Since the D5000 is older and less expensive, will I notice a huge downgrade from what I'm used to using? I'm sort of a beginner, but I want to have good features available to me so I can learn more about it.
So how good of a camera is it? I'm mainly going to be using it for artsy photos and vacation photos. Also, does it shoot in burst mode?

I don't use Nikon - Canon is my deal. I'm told it's a good camera. I wouldn't expect a huge difference, after all these are all dslr cameras.

The D5000 is actually the newest out of the cameras you listed. It is, however, more entry level.
Something good about it is that Nikon recycled the sensor from the D90 and popped it into the D5000. You will get near D90 quality in your photography.
as for burst mode, I do not know, but you can definitely read all about it here:
http://www.kenrockwell.com/.../d5000.htm

D5000 is a great camera. It is much newer than the D80 and D90, and is pretty close to the D90 in terms of actual performance. It lacks the wireless flash commander mode, built-in focusing motor, top-deck status display, front command dial, that the cameras you are used to have. It also has fewer dedicated buttons, meaning that you'll have to use the menu a bit more to get to some of the lesser-used functions.
I should mention that the lack of focusing motor just means that all AF-S and AF-I lenses will focus with it, but older screw-drive AF lenses will not.

It is a great camera. The D90 has two adjustment dials; one for aperture and one for shutter. The D5000 is missing the second dial so you have to hold a button while adjusting the single dial. If you don't shoot in full manual, this won't be any issue. If you like full manual, you would appreciate the D90 or D7000 more. Quality should be the same.

I doubt you'd notice a huge downgrade from the cameras you're used to using. If you're a more advanced user that shoots in S, A, or M mode and often change your ISO or white balance settings, you'll find the D5000 will take longer to change those settings because more of the options are accessed through the menu. Other than that, there's not really a difference other than its smaller and lighter. The D5000 does shoot in burst mode at 3 fps.