This is a very useful feature and it is working great so far. @James in your related blog post (9 ways to use . . .) you mentioned sending tasks with Do Note, which is one of the main ways I intend to use this new feature from my phone.
Do Note has the limitation that it accepts only one block of text in the message which, depending on the Gmail channel recipe, (1) puts that block of text in both the subject and body text, or (2) uses the recipe's "canned" subject line and places the text block in the body.
Both of these Do Note methods have the limitation of not allowing GTDNext to do what it is meant to do by placing the Subject of an email in the new Task line and the Body in the Notes. If anyone finds a Do Note workaround for this please post it here. Thanks.