back in the n800 days, I used the stylus keyboard for some things (vi, notes, email authoring) ... but I used the thumb keyboard for others (mainly IMs). For some things, the stylus keyboard was better, and for others, the thumb keyboard was better.

My opinion would pretty much be: definitely make sure you have the capability for _both_. I can't imagine Mer being successful, on devices that have no physical keyboard, if it can't do both stylus and thumb keyboard input.