SilkAir announced they signed a LoI with Boeing for 23 B737-800 and 31 B737MAX-8 with another 14 options. The orders can be converted to other versions.
This is significant as Silkair is the first customer Boeing catched from Airbus. Silkair currently operates a fleet of 21 A320 with 3 more on order.
Until now it was Airbus who draw customers away from Boeing, the first one being American Airlines - prompting Boeing to announce the (then yet unnamed) B737MAX.