Excellent! I'm glad that we're on the same page here. Thanks for making the service, once the single point of trust (your client) is removed I should be able to fully recommend it to everyone I want to communicate with.

Just a thought: I like how you walk the user through the steps you took to prove that the owner of the private key signed the tweet. I suggest you also provide the appropriate commands to perform the verification ourselves as well. The client does this, but for users operating without it it'll be very useful.