Google has hired the developer of SynthCam, which is IMO the most interesting computational bokeh app. Combine that with the ability of the mems system and a fast image sensor to capture images at every focus point and estimate depth based on what is in focus in each image. You can then pick what you want blurry and what you want in focus and even how blurry you want the blurry parts to be. I hope they can make this all seamless in the nexus 5.