I find the on-screen keyboard just fine, even on my N810.

I spent a LONG time working on an alternate form of writing characters -- I forget what it is called -- and it was completely intolerable, even after weeks of intensive, fanatical practice.

I liked Graffiti quite a bit at one time, but I think that if one gets serious, none of this approaches the ease of typing on a regular, full-sized keyboard. Where I'm typing now, I don't have to think, and I get up to 70 w.p.m. without effort. Of course, I'm on a desktop computer, not a tablet.

In the long run, I still think that speech-to-text will work out eventually on tablets, when processor speed becomes sufficient. I have Dragon NaturallySpeaking on this desktop, and it is pretty amazing.

For professional, extensive typing, a desktop computer is best, and a big screen helps too, like 19 inches or so, though it's hard to fit in your pocket