[itsbanderson]

This is a good point, and something we definitely consider. Our A/B testing tool, ABBA, performs the necessary statistics and is mentioned in the "Test everything" section of the post.

[thejosh]

ABBA is a fantastic name for a A/B testing tool. Props to the creators for that name.

[itsbanderson]

ABBA: http://www.thumbtack.com/labs/abba