Earlier last week Adobe released an update to Lightroom CC and Camera Raw with the major feature being a new control called "dehaze". As the name implies, with a single slider it can help make your hazy (i.e. washed out, low contrast, low saturated) images less so. Thats when you push the slider to the right, take it to the left and images become even hazier. I've been playing with it on a several images and its a pretty useful tool to have in a single slider. This is what the image looks like with only the haze slider set to 0.
It looks to me like the one slider increased contrast (at multiple scales) and saturation. Interestingly, since increasing contrast changes tonal relationships, I would actually have expected this control to be up in the "Basic" settings area rather than down in Effects (with Vignette). I find dehaze to generally do a good job on most images, so its actually the first thing I want to try, and then go fix up the tonal relationships afterwards. I haven't tried going negative on many images but on the ones I have I almost always want the ability to do it selectively (i.e. with the radial filter or brush). Overall, I like this new tool and I think it should just be called "bacon" because a little bit makes almost every photo taste better.