Obviously building an sampled instrument (as opposed to just providing the samples) is time consuming, and producers and devs will gravitate towards the formats that provide the most exposure. Obviously Knotakt's been around a while, has great scripting facilities, etc., It seems to be increasing in popularity to the extent that it's becoming the de facto standard.
Related - I love Live's ability to collect and save samples as part of a project in Racks - you can work with an external drive and bring samples in easily without re-mapping. How well does Kontakt handle sample library management?
(I know - sample management is a key part of a sampling instrument

