One of the most frequently used iPhone Today View widgets on my iPhone is the Hue App. It isn't anything particularly special but with a quick flick down, I can can turn the lights on (and off), which is nice and faster than opening an app and navigating to buttons.
The interesting part to me is how second nature this has become. Doing the home screen posts, I find people either love using widgets or don't use them at all. I'd be interested to know how many people actively use Today View widgets. I'm guessing it's a pretty small percentage of overall iPhone owners and that may explain why Apple has backed off it's initial, conservative stance with respect to widget approval. I also have to wonder if the Apple Watch may wake people up to just how handy widgets can be on all of the iOS devices.