nope, that works. 25 new messages since yesterday.
So this thread has informed me.
This is a case where I tried something Siri related and, as the odds favor, it didn't work, so I never tried that thing again.
And that's kind of my point. I do not feel, as a potential user of Siri, that it's improving at any measurable rate where I think a re-attempt is in order. In iOS6, if it couldn't do stuff, I forgave. In iOS7, there wasn't much publicized improvement, so I carried on with my same old set of stock commands: "Set alarm for...", or "Call [person]". That's just about it. iOS8? Did they mention Siri?
But after two years of saying "Play a Pink Floyd album", and it just shuffles up every Pink Floyd song, I just quit trying anymore. The guys at Apple will never translate the command "play a [artist] [album]" to mean something other than "play any ol' [artist] song" despite likely having loads of records in their database of failed user intent translation. Siri may become like Dashboard - absorbed, promoted, demoted, and forgotten.
But, yes, evidently, NOW it shows me my Mail, but it didn't used to, and nothing made me ever want to try again, except this thread. And that is the failure here- the loss of expectation or even experimentation. I don't expect Siri to work for commands other than I know it knows, so I do not try.