I use my iPad all the time, David.  I no longer travel with my laptop.  Music, email, web surfing, blogging...  I can write, edit, re-write and toss away anything I want.  But, tbh, I wouldn't want to write a book or edit it on an iPad or anything like it.  I love my MacBook Pro hooked up to a 24" HD monitor for doing all my writing and research in two-screen heaven.  I won't be upgrading to iPad 2, though.  I have all the camera I need in my iPhone.