Horace Dediu on siri:

However, it does seem to be good in a very limited set of tasks. It is something you can hire for some minor jobs that you’d rather not do. Basic calendar booking, context aware search and a few delightful surprises. But it’s not trying to be much more. It’s not trying to be a typist. It’s not trying to be a companion. It’s not trying to be smarter than you and make you redundant. It’s only trying to help lubricate your life. This is what makes it so exciting.