Being right and sounding right are two important but separate skills in natural language communication. It sounds like they've nailed one of them and the other is somewhat hit and miss right now. To me it's obvious that there's no reasoning going on behind the curtain, but in a lot of domains that doesn't matter. You don't need your answering machine to opine on philosophy questions just like you don't need your mechanic to invent and machine a custom part every time you bring your car in.

(Edit: Point being if you can back the chatty part with something that's actually an expert in the domain you need it to talk about, then you've got cold fusion.)

I don't think it's ready for prime time yet, but the way voice recognition and synthesis, ML, and scalable computing power have been going in the past several years, we're not far off. And that's incredible.