Seemed like such a long shot, just a few months ago.. especially in October when Adam Back was predicting $100k before the halvening, and now even he is not looking so crazy.
At the time when I read about Adam Back's bet on the 100k I thought he was crazy for betting that, unless he had some privileged information, which I think is difficult... at that time bitcoin was in the region of 30k. It was impossible for such a bold bet to succeed, nowadays I think it could be completely viable.