I do understand the tactile feedback is nice. A long time ago I got an HTC pocketpc with slide-out keyboard for the same reasons, but I felt the clicking also slowed me down. For the small screen on that particular device the tedious stylus and finger entry was slower, so the keyboard was a plus. But with bigger mobile screens nowadays finger or stylus entry is less of an issue (especially with smart entry hacks). For keyboard entry for typing longer e-mails or ssh access I now only use an external keyboard where I can use 10 fingers instead of 2 thumbs - for the same reason I prefer a frogpad to a twiddler for one-handed entry.
Writing anything beyond SMS-length on a touch device, I end up popping the keyboard up and down repeatedly to give what I'm writing a useful amount of screen space. With swipe entry, my raw input speeds of English are much better than with some kind of thumbpad, but watching the keyboard still means ignoring what I'm typing and going back to fix typos.
I like how touchscreen swipe input seems to flow. I like how a physical keypad can be used without necessarily looking at it, and how it doesn't reduce the view of what I'm writing. I haven't used a stylus interface that I've particularly liked because it seems like the worst of both worlds.
All those together are why I also do my best to avoid writing anything sizable on a mobile device.
