I got the laptop a few days ago. Overall, it's a mixed experience.
The touch screen has problems with a clean install of Ubuntu NE 10.10. Some (private) people is working on it - informations here.
Also the function keys have a very annoying problem.
Disappointing. Although it's "usable" (keeping in mind that as long as one sees something on a screen, it is "usable" by definition), the vertical range is very limited. This prevents the screen to be used in portrait mode, because the right part is darker than the left one, unless you keep the left farther than the right when you read.
10 inches are also a bit narrow, although this is a subjective opinion.
As a matter of fact, when I use it to read on the bed, I use it in landscape mode.
The N550 Atom platform is not slow itself. On a clean Windows 7 I felt it as responsive and didn't experience lag during regular desktop usage.
The Ubuntu NE 10.10 [Desktop interface] as system instead is slow and unresponsive, although usable.
Always speaking about Ubuntu, the applications theirselves are fast enough - for example I tried some 480p videos in youtube and they were smooth; same thing for common applications like OpenOffice. Firefox is acceptably fast using a few tabs, but no more than around 4.
So it all boils down to the O/S: I would recommend it for Windows users, but absolutely not for linux ones.
Some reviews around describe the machine as slow on Windows 7; keep in mind that they always refer to the pre-installed Windows 7, which I believe is full of junk and, certainly, has a terribly programmed custom interface.
The construction is cheap.
The fan is noisy.
The lid around the screen is a bit too thick.
If you're used to SSD disks, you will feel the disk rotation.
The weight is reasonable for a hybrid laptop (~1.5 kg): light if compared to full tablet pcs, heavy if compared to tablets.
Objectively speaking, the laptop is a bit heavy for "demanding tablet usages" (ie. bed reading), but I got used to.
I feel that the lid however is robust enough not to break with the usage.
The keyboard is pleasant.
The laptop makes sense for what is being sold, that is, a cheap tablet with the premium price of an innovation.
I just noticed that Asus is going to produce the Eee Pad EP121, which according to this page, compared to the Inspiron weighs around 70% of it, it has a bigger screen, a more powerful CPU, and an SSD disk. Essentially, price aside, it wins hands off.
I specifically purchased it because I needed a "powerful" tablet without spending too much. Wrapping up, I got what I wanted - it may satisfy your use cases as well.
If the Asus Eee Pad EP121 would have been out though, I would have chosen the latter.