The problem with linux is that it is hard to use. Most people don't care that you can do miracles. They only know about miracles you can do by pressing a button. Not miracles you can do bu using terminal and writing complicated scripts. This is why the iphone did so great. It is so simple to use that even idiots can use it.

The N900 is better than the iphone or android in my opinion. It can do more things. But how many people are able to do these things? Only if you have a fair bit of linux background are you able to do such things.

So the next device in my opinion should be compatible with idiots to succeed. So simple that even a kid could use most of its functions.