Really not a bad bargain..
I just picked one up along with the Magic Trackpad, which I LOVE, btw... It was there, alongside the trackpad and the Magic Mouse and Wireless Keyboards at the Apple store. It really makes a fine companion product. It comes with six batteries. It is very compact, sleek, and a good value. I will probably never have to buy AA batteries again. 2 will be for my trackpad, 1 for my toothbrush, and alternate the other 2 between my bike light and beard trimmer.
Nobody is being forced to purchase this charger. If you can afford it, want it, then get it. If not, don't and get some other make. The trackpad is really great. I don't know how long the batteries will last per charge, but when I do I will report back. The batteries are made in Japan, also. The charger in China, but designed in california by Apple, not some other fly by night outfit. lol.
If you do get it, I think you will be happy you did. Cheers!