On a WSJ video, Ed Colligan of Palm says that "sometimes you want simplified computing" in providing a raison d'être for the Foleo. On the Palm.com Web site it says something such as the Foleo is made for that 2-day business trip to Boston, the conference across town, or the meeting down the hall. This seems to suggest that you will buy this in addition to your heavier laptop computer.
He also states that "...you'll see very quickly thousands of applications..." produced by the developer community. This might suggest that this product is a "mobile companion" looking to grow into a simplified laptop computer, if all this vaporware should actually become realized. Has this can be applied to a vertical market such as healthcare is hard to predict. The flavor of Linux the Foleo supports is not mentioned.
Since reports say that the Documents To Go software installed on the Foleo allows you to create (I don't think this applies to PowerPoint), view and edit Office documents which you can access as an e-mail attachment, from the Treo's memory via Bluetooth, or from an SD card, this seems like a workable solution for a student who doesn't have a big budget for a portable notetaking device. As a device for a business professional, or blogger, or really anyone else who is used to the functionality of a Mac or a PC, I think the shortcomings of this device will quickly become apparent, overshadowing it's instant on/off feature.
If the intent is to begin the process of creating a simplified, Linux notebook computer, it's an admirable one, but requires a big commitment from the users and developers that isn't as yet apparent.
BTW, the smartphone meme is not dead, and most Treo fans are waiting for the new, improved version. The keyboard problem is not a universal one.
The killer app to come will be speech recognition on a handheld device which will solve the keyboard, not the large screen problem. Right now you can dictate into a voice recorder and then have it automatically transcribe when you dock it on your sufficiently powered PC (at least 2 GB of RAM and fast processor). If the OQO2, the FlipStart, the HTC Shift ever become this powerful, you'll have a most impressive most device, or you can buy a $70 Bluetooth portable keyboard to add to your $1800 UMPC.