A few random comments...
- You really ought to get yourself a laptop.
I'm typing this from my laptop which is on my lap as I sit on my couch. I've got 802.11g Wi-Fi in my house. I usually spend all of my computer time on either my couch or my bed. Downsides: my wife thinks I spend too much time on the computer.
- The IBM trackpoint (the eraserhead pointing stick that you referred to) is one of the world's greatest invention and I'm sad that there are only a handful of companies that make use of it. I hate touchpads. I recognize that the trackpoint is hated by many. It seems to be one of those things that people either love or hate. A foldable QWERTY keyboard with a trackpoint is long overdue.
- Take a look at
FieldPlus for the Treo. It promises to let you select text using the shift key and the D-Pad. I've been too lazy to get around to installing it myself (so I can't comment yet as to how well it works), as I don't do word processing on my Treo, but I'll probably install it since I do often have a need to select something to copy and paste. It's freeware.
I can't comment too much on the rest of your article as I've never had much need/desire to do word processing on my PDAs (I use my laptop for that sort of thing). But please do write more articles discussing your ideas for improving usability on mobile devices as that's something I enjoy reading and writing about.