From using and developing for the Amazon Echo for the last year or so this "Conversational" setup just sounds super unnatural.
You want bus times: Amazon: "Alexa, ask [nextbus] [for the next bus]" Google: "Hey Google, let me talk to [nextbus] <wait> when is the next bus?" Perfect: "[keyword], when is the next bus?" (context set in advance for the specific bus you care about)
You want to control the lights: Amazon: "Alexa, turn off the [kitchen lights]" Google: "Hey Google, let me talk to [the house] <wait> [turn off] the [kitchen lights]" Perfect: "[keyword], turn off the lights" (contextually turn off the lights immediately nearest the source of the voice. optionally "turn off the [named] light"
You want to activate a scene: Amazon: "Alexa, [turn on|activate|start] [scene name]" Google: "Hey Google, let me talk to [the house] <wait> activate [scene name] Perfect: "[keyword], [time for a movie|it's bedtime|good morning]"
I haven't seen or heard of a single "Conversational" app for the Echo that has real usage. I just don't think that's the killer app (at least until they get smarter). The current killer apps are being able to: - Set timers/alarms - Ask quick questions (measurements, weather, time) - Control home automation
I just don't think the experience of talking back and forth to a bot is that enjoyable (again, yet, maybe in a Her future).