Here's what Anonymous had to say about it:
I've observed a fair number of different automated stop announcements on various train systems over the years. The best systems limit the announcements to just three things:
1) As you approach a station, providing the name of the station ("This is Oakville station")
2) At the station, providing the crucial information about the train for those boarding ("This is an eastbound train to Union station")
3) As you pull away from a station, providing the name of the next station ("The next station is Clarkson")
... AND THAT IS IT.
You'll notice the ideal matches pretty nicely with what CSA does now. However, I worry that someone at Metrolinx/GO will feel compelled to add a large amount of surplus information, and we'll end up with something like the external announcements on GO Buses ("Thank-you for pre-purchasing your fare. For passengers using Presto, please have your card ready. Thank-you for choosing GO Transit").
I'm hoping GO Transit doesn't overengineer this either. No feet on the seats reminder -- next stop -- and then shut the hell up -- works for me.