Alexa

Does anyone know when the Alexa app is going to launch..?

The people who know aren't telling.

Much like all other things that Sonos works on. The only thing that they've committed to is it will be out in 2017. We still have several months of that. Who knows, it could be tomorrow, or it could be December 31.

I'd be willing to bet they're doing everything they can to have it out ASAP, as I think it would have a major impact on the Holiday sales, which seem to start sometime before Thanksgiving, here in the US (that's early Novemberish for those of you elsewhere, since Thanksgiving is the 4th Thursday of November)

As a general rule, Sonos don't like to push firmware updates too close to the end of the year, to reduce regression risk to a pile of new holiday customers. So lets assume an RTM date of the end of November at the latest. To do that, a public beta of, say 3 months, would need to start around the end of August.

A further complication is Amazon: from the demo we have all seen, Amazon need to update the Skills infrastructure and the firmware on every Alexa device to support Sonos without the wake word. Amazon are very slow at rolling out system-wide updates such as this, but they would need to do that before any Sonos public beta.

Yet another complication is music services: for this to work well, SMAPI needs an update IMHO, and then the main music services will need to implement the new speech-friendly search.

So the next thing to look for as a timing clue is Amazon pushing Alexa updates to handle Sonos-like Skills. Once that happens, we can assume the clock is really running for the full stack: public Sonos beta, music service/SMAPI updates, then public release.

This all assumes USA-only of course. While Sonos have a good record of multiple language support for localization, Amazon have a terrible record for non-US skills, plus the necessary speech-localization that Sonos need to do is a lot harder than product-localization they have done previously.

This would put the release pretty close to when Engadget says Amazon plans to release their new higher fidelity "Homepod Killer" Echo speaker. I wonder if all of these releases are linked somehow on the Amazon side so that they need to happen together?

[...] This all assumes USA-only of course. While Sonos have a good record of multiple language support for localization, Amazon have a terrible record for non-US skills, plus the necessary speech-localization that Sonos need to do is a lot harder than product-localization they have done previously.
I don't think Sonos will be supporting IoT skills with the integration if it's that what you mean. It's a Multiroom-HiFi-System – no more, no less.

Does anyone know when the Alexa app is going to launch..?

And when it does appear brace yourself for the predictable, let's not use any brains at all, non-stop whining and whinging tirades about how it doesn't do this, that, put the cat out or iron the curtains rather than what it can do. I shall have to practice sighing.
Interesting times await. As does the purchase of yet more Dots.