Braintoss is an amazing app.. it is in my Dock because I use it all the time. I use it in combination with my OmniFocus email address to send myself tasks faster than I can do with the OmniFocus app. You only need to set the email address once and Braintoss will do the rest for you. It even transcribes audio!
Braintoss is developed by Email Handyman to complement a straight forward way of capturing To Do's and other thoughts and toss them straight into your inbox. From here, using the Email Handyman process of emptying your inbox (or GTD or Inbox Zero) the tossed thoughts are included in the process of managing tasks and setting priorities.
So what about Evernote and Siri? Simple. Braintoss was developed to be the easiest way to drop whatever is on your mind into your inbox. NO further categorizing, no further discussion on what you just said. Simply dump it in your inbox for further processing (which could be forwarding it to Evernote) when you are back in the office or have time to deal with it. Forget about it for now and action, forward or file later.