This is probably old news but I just discovered that Siri in iOS 10 is dummer than Siri in iOS 9.
While running iOS 9, if I heard a song I like but didn't know anything about it, I could always ask Siri, "What's playing?", then after a brief listen Siri would tell me the title of the song and who performed it. But in iOS 10 Siri says it can't identify the song because I don't have any music loaded in my phone. I suspect that it wouldn't matter a whit if I had my whole music library loaded, because they removed the Shazam app.
Yes I know I could always install Shazam, but it was so much more convenient on several levels to just ask Siri.
The last time I tried Shazam, it wanted my email address, then I started getting unwanted email crap from Shazam's developers. I tried several times to opt out of their emails, but finally had to just create a filter in my gmail account to delete their emails from the server.
I'm sorry but I refuse to do business of any kind, even if it's free, with anyone that feels they have to spam me with email crap that I can't opt out of.