I was about to reply that stacks is a new feature, but I googled it and found it's been a feature since 2007. I could have sworn it was announced a year or two

I was about to reply that stacks is a new feature, but I googled it and found it's been a feature since 2007. I could have sworn it was announced a year or two ago. Anyone know if there was an improvement announced recently that I seem to be recalling?