Verified answer

The only camera where a grip does add more fps that I can think of is the d300

The MB-D10 will not work on your camera, it works with the D300, D300s, and D700. The grip won't even work with your D5000's battery. It can use EN-EL3e or EN-EL4a batteries. Your D5000 uses EN-EL9a batteries.

You have to go to the aftermarket for a battery grip as being an entry-level camera, Nikon does not make a battery grip for your camera.

http://www.nikonusa.com/Nikon-Products/Photography...

At any rate, a battery grip will not increase the frame per second rate. It just allows you to have longer battery life, and in some cases, use AA batteries for backup. And at least for the Nikon grips, they add a second shutter release and control wheels (the aftermarket ones vary on these features).

Many people use a battery grip because it looks cool, but it just ends up making the camera heavier.

I have MB-D80 a battery grip for my D90 but I rarely use it. I only use it when I am using my Nikon 80-200 f/2.8 as this is a very heavy lens, and the battery grip helps center the weight distribution and balance.