We released Drupal Commerce 2.0-beta1 at DrupalCon Dublin one year ago. Over the next 9 months we tagged 6 more beta releases comprising over 500 commits by 70 different contributors working for at least 10 different companies.
The Drupal Commerce 2.x development process has been one big adventure! Over the last 2.5 years we've accumulated 2,000 code commits in multiple repositories from over 70 contributors at dozens of agencies.
Square's pitch is pretty straightforward: accept payments anywhere, no coding required. They nailed this first through their simple phone based card readers and their slick in-store tablet interface.
Commerce Guys has long been a leader in the development of e-commerce websites using Drupal, with our flagship Drupal Commerce project running on over 60,000 sites.