Re: I use Siri all the time
Yes improving speed should be their No.1 priority. General as this article notes I've noticed accuracy has improved. The main areas of improvement since launch is in the ability to launch apps and control OS features and settings. Another big improvement that is actually pretty cool tech-wise involves the way Apple have adapted Multipath-TCP to ensure Siri maintains a connection even when you are passing into or out of WiFi hotspots (which may grab your WiFi with a login screen). I became aware of this improvement because the time I use Siri most is if I am running late, when I leave my apartment I exit out of my WiFi range, then cross back into it as I walk past the front of the Apartment, but with weak signal so the connection often doesn't work properly, then leave it again. This sequence used to destroy any Siri requests so my "Hi X I'm running late" or "Hi X meet you at 7:00pm" type messages would fail. Now they succeed, which when you understand the problem and the process gone through to get around it, that the solution works so well is quite impressive. This same connection robustness ensures connections are maintained for other over-IP services like FaceTime.
Having said all that, it still remains that I only use Siri limited to pretty much the following cases 1) requesting preferred tracks are played (but only if I'm not in company, I still feel too self conscious making such requests in a crowded place) 2) To set timers when cooking 3) To send "running late" style messages 4) To listen to received text messages and voice messages when on the move (saying "read me that text message" works pretty well). I know it can do a lot more, but I think the problem is, with a voice interface, since you can't "see" new features, you tend to establish a pattern of use and then find yourself sticking with it.