I think it just goes along with the Note becoming a more mainstream phone instead of a powerhouse like it used to. In the past the Note was the most powerful phone you can get at the time of release, now it's pretty much on par with other top handsets while offering other cool features, like awesome camera, screen, and design. You no longer get the note because of speed, you get it because of those other features.
That being said, in benchmarks my Note ranks among the tops of android handsets, so it's more a software optimization, because the hardware is there.