Forgive me if this has been covered elsewhere. Have their been rumors or announcements around using Echo for voice announcements through ST. Particularly choosing a specific room to make those announcements in.
Is this something that could be accomplished in a firmware update?
You can do this now with either of two community-created smart apps: ask Alexa and EchoSistant. Setup is fairly complex and you will have to create an Amazon developers account, but it can be done. Both are listed on the quick browse lists for smart apps in the community â created wiki on The Voice list:
As far as an official text to speech (TTS) feature from Amazon, lots of people want it. 
Make sure you put in feedback through the Amazon Alexa app that you want to see it. Amazon doesnât announce in advance what theyâre working on, but it does seem likely that this will arrive eventually.
As for pushing messages actually to an echo type device⌠A little bird told me⌠Donât hold your breathâŚ
As Jason said, it HAS been announced in the news, but it may not happen. The fact that Google Home was released without this feature tells me there is great concern in the industry about devices that just ârandomlyâ talk.
My app Ask Alexa, is ready to implement this feature should it ever be released.
There are custom ways to make GH wake up and speak based on events using the cast functionality, is there nothing similar for Echo?
There are by pairing with a cell phone and Bluetooth.
Yes, with an android device and LANnouncer. Itâs not as âsmartâ as the previous two I mentioned, but it serves well for just 'casting.
Weâre getting passed devices that are always listening. If we want the future, gotta take some leaps.
Yeah, inside news says that itâs legalities that are the problem⌠Not sure what legal issues⌠But⌠LawyersâŚlol
Once itâs released it should be an adjustment to the apps. EchoSistant is ready for it as well.
But, itâs probably a very long way off.
Unless Iâm missing something, seems that if they give the user the ability to turn push messages off, there shouldnât be anything to worry the lawyers.
The Ubi had this capability and I used it for both IFTTT and ST notifications. I absolutely LOVED it (until my Ubi died), as I could throttle it based on what I cared about and how angry my wife was with the house talking to us. As long as any capability is opt-in, it greatly expands the HA capabilities.
Quiet down before my wife hears you. She just assumed that the BT speakers I stashed around the house attached to the control panel Fires with lanouncer are just an Alexa update & itâs Alexa talking back to her.
Love both my Ubis, they were the first Echo devices and they can be has as cheap as $25 on Ebay NIB. 
I strongly encourage anyone who has 5 minutes to âformally requestâ this to Amazon / feature request at this site â the more voices the quicker the upward mobility for prioritizing.
And as many on here have stated - AMAZON is very aware of this feature request. It is the policy of Amazon to not disclose roadmaps.
I worked hard on this and finally got it all working with Lanouncer and Big Talker to only realize that I was the ONLY one interested in this. The ENTIRE family got together to have a âSit-Downâ with me to politely ask me to tell âAlexaâ to STFU!
WelpâŚthat was that.
Just gotta tune it. Probably annoying at first until you pare it back and they realize itâs useful. Find the balance for the family.
Yeah definitely throttle back the notifications, they can get old fast.
But push the idea of security. I canât see my front door from the rest of the house, so being told it is open is a good thing. Iâd never do it for my back door, it would never stop talking.
Try to find things that the family would like to do. When my kids come home their rooms are all powered on. My wife never comes home to a dark house.
Good luck