It's absolutely spectacular. It's quite possibly the best computer I have ever owned.
I have had a Pandora for over a year and I agree with the above. It is a fantastic device for many reasons and I just love it. For the size, for the ready made programs and games available from the repository all neatly packaged for the pandora, for the very usable keyboard and great gaming controls, for the very friendly and productive community, for the exceptional battery life. Also it has an up to date firefox on the unit and I can use the pentadactyl add-on to give me vim style keyboard control of the browser.
There is more information to be found on the forums at openpandor.org The Pandora may be physicaly small, and the case does look a bit ordinary, but with it you get a lot, and there are still lots more that I could explore on the unit.
Especially for someone like myself, I travel a lot and have to travel light. I must take a company laptop filled with company software, I cannot mess to much with the company laptop, I need to produce official certificates and reports on this. There is really not enough room for another laptop in the bag.
The Pandora fits easily as an extra. I can play games, browse the internet, write some code, play some music, watch a film. It comes with me every time I travel.
I agree that it is not for everyone, and that is fine because it is great for a lot of us, there is no one device that fits all.