Congratulation on shipping! The experience was flawless and quick.
Two things I noticed which I hope you will consider fixing:
- It was trivially easy to expose the user's google/gmail address by typing in a random URL within the user's blog. The 404 page exposes the user's email address. [0] Probably better to have some UUID-email mapping that is secret.
- When I clicked "Delete Account/Blog", the application did not remove itself from Google's "Apps with access to your account" page and was still showing up as an active integration.