[delphin]

I agree that the Nook will give you trouble outdoors, as will the iPad.

Tablets with backlit TFT LCD screens are just too battery challenged to crank up the screen brightness enough for viewing in full sun.

If you really need outdoor usability, and can live with a device in a slightly larger form factor, I have found that many of the newer Netbook PC's remain fairly usable outdoors.

Still not great in full direct sun, but at least usable.

The difference is the battery capacity -

iPad -> 25 watt hours

Nook Color -> 14.8 watt hours

Netbook PC -> 48 watt hour battery standard, and you can carry a spare battery, with up to 63 watt hour replacement batteries available.

This extra juice lets the Netbooks offer more screen brightness, and by overriding the power save settings and setting my netbook's screen to full brightness, I can still read or work for hours outdoors if needed.

Because of the brighter screen, my Netbook looks great in indirect sun, like under an awning at an outdoor cafe, and remains at least marginally legible in full sun (where the Nook Color is essentially useless).

By way of comparison in bright indirect sun, a Nook Color will be just barely usable (ok in a pinch, but not something you would want to use on a regular basis), and in full direct sunlight both the iPad and Nook Color become basically useless.

Of course the tradeoff is size. Open, my netbook is about the size and weight of medium sized hardback book, but still offers a nearly full sized keyboard, which meets my needs for both usability and portability, but may not meet yours.

With Netbook prices falling as tablets become more popular though, I was able to pick up BOTH a Sony PRS-650 AND a nice Netbook for less than the price of even the most basic iPad.

This gives me an eInk device that works great in full sun and has weeks of battery life, and a portable color e-reader with great video/web-surfing capability, and enough screen brightness and battery capacity to work for hours outdoors in a pinch.

The iPad has some pretty amazing apps, and Android tablets are getting better all the time, but it will be awhile before they can match the versatility that I get from my netbook which I have set up to run both Ubuntu and Windows 7, plus XP and Android in VirtualBox. (Some folks don't realize that Netbooks can also run Android apps, as there is now an open-source x86 version of Android that runs on netbooks.)

Tablets like the Nook Color have a very attractive form factor that does fill a definite need, but in the end, after trying the Nook, I decided that I would go with a proven technology in the form of a PC compatible netbook device, and wait until the tablet technology matures a little bit more.

Edit :

The iPad and Nook Color look great INDOORS, with the iPad having the edge on screen legibility due to it's larger size (and of course the Nook Color having the edge on portability due to it's smaller form factor.)

But OUTDOORS, both the Nook Color and iPad have serious issues because their screens can't pump out enough brightness.

Bottom line - all tablet devices are limited on battery capacity, and even with efficient LED back-lit LCD screens, until there is a breakthrough in screen technology of some sort, there are going to be issues with using the devices in direct sunlight.

If you MUST use the device outdoors, a Netbook with a brighter screen may be an option, but they are not all created equal, so you may need to compare and audition several devices first to find one that will work well outdoors.

An eInk device will work great outdoors, but currently eInk color technology is not widely available so most of the available devices are black and white.

Color eInk devices are coming (google eInk Triton and Mirasol to keep tabs), so for now I will use my netbook, and wait for the color eInk tablet technology to improve.

An absolutely KILLER PRODUCT, for example, would be a 'flipable' iPad with a color eInk Triton screen on one side, and something like the current TFT LCD on the other side.

When not in use, the ePaper side could display a nice 'skin' graphic, and the orientation sensor could be set to automatically disable the power hungry TFT LCD and activate the eInk display when you flip the device over in bright outdoor conditions.

If Apple doesn't offer such a tablet, one of the dozens of Android manufactures is sure to do so, so the good news is, sooner or later, we will be able to 'have our cake and eat it too' when it comes to both indoor and outdoor usability