The 16ga "cult"--although it's pretty much that--has actually gotten stronger in recent years. Comparing gun choice by gauge in data provided by LODGH (Loyal Order of Dedicated Grouse Hunters): Back in 1983, 9% chose the 16. In 2012, that was up to 15%. On the other hand . . . over the same period of time, the 28ga has taken a HUGE jump in popularity with grouse hunters, per LODGH data: from a blip on the radar 1% in 1983 to 13% in 2012. I'm sure part of that is due to the fact that there are a lot more 28ga field guns available now vs then. Most 28's back then were skeet guns.

But the top choice among LODGH members has scarcely changed over 30 years. Right around half of them prefer the 20ga.