Preliminary work went into getting DuctDo started. For faster development, I always find it easier to get a bare bones website up and running so that I know what my minimum feature set needs to be. Beta DuctDo is up with a template from OpenSourceTemplates letting me focus on the content and not the design side. From here, I will bash out simple things.
Sign up - I need to let users sign up with just an email address.
Log in - Needs to be fast and easy. Email verification is critical, so I'll ask for the password after they've verified.
Goals - I need goal creation to be fast and easy. After their first log in, they are asked to create a daily task or goal they want to achieve.
Timezone - I need to grab their timezone and setup intelligent defaults. An email sent out at around 6-7 AM in the morning, and a 6-8PM end-of-day email seeking feedback.
Email Reply - Allow for the user to reply to the email response with a written commentary. Maybe a simple link based system where they are taken to a page where they can fill in their response as well.
Published results - Each user should have an easy to view log of the results, published.
Calendar - To show each day they succeeded in doing what they set out to do.
That's the bare minimum, I think. Allowing for Facebook and Twitter connection is important, but no need for an immediate setup.