I do not think they are overpriced.
I have a Unibody 13" Macbook Pro that I bought last summer.
It is a 2.26GHz C2D with 2 GB of ram. It came with a 160GB hard drive that I upgraded to 500GB myself. It has an nVidia 9400m graphics card. It is also extremely well made aluminum with a backlit keyboard and 8 hours of battery life. Yes I actually have gotten close to 8 hours of use.
Try and find a comparable computer from another company. Keep build quality and battery life in mind and I don't think you can even find a comparable laptop, much less at the same price.
Also if you buy during the summer with an educational discount its $1100 with a free after rebate iPod. I sold the iPod on eBay for $200 and ended up paying $900 for the laptop plus $100 for the 500GB drive.
$1000 for a great laptop with great build quality with solid specs is a pretty good deal, regardless of OS or manufacturer.
Super expensive laptop batteries have always bothered me.
If you've ever taken one apart you know whats inside them. A bunch of AA cells strung together in series. Thats it. They're not top of the line Energizer or Duracell either, they are the cheapest of the cheap AA lithium ion cells mass produced in china or japan or where ever is cheapest at the moment. They are worth no more than $5 in total. Its appalling how much these companies charge for trash.
This isn't to say all companies use such shit. There are a few that custom make their own batteries for better performance and size.