I just bought an old HP Pre3 and I must admit that I am quite impressed. Compared to the N900, it lacks an extendable memory and a stylus (and a terminal ATM) but on the other Hand, Web OS is quite nice.

As far as I am aware, Palm/HP Pre phones are the only devices that combine a good, one hand usable touch OS (and a screen size supporting one-handed use) with a HW Keyboard in a meaningful way.

In fact, my wife, my mother-in-law and others now want a Pre phone because they are so much easier to use than their Android phone. I tried to talk them away, because otherwise I had to provide all the support that is no more available from HP.

There IS a market for these devices and it is really the question who will be the first to serve this market.