Here's one for the bug report section of Applevis.
A friend on twitter told me about this yesterday so I tried it myself and I get the exact same results every time. Note, this bug appears in iOS 8.2, I haven't seen this happen with earlier versions.
To reproduce this bug, do the following...
1. Ask Siri to set an appointment for you. I picked the random hour of 9 AM just for fun.
2. She will confirm that it's the right time and you can confirm once again. I answered no to the question about it being a scheduled appointment, because it was only a test.
3. Siri will now say, uh oh, there seems to be a problem. Can you try that again?
4. Now, go to your calendar and look up the date and time you specified for the appointment, and you'll see that it's been added to the calendar, despite Siri saying there's a problem. I went ahead and deleted the appointment, once again it was a test so it really didn't matter. Has anyone else seen this? It happens every single time I try it.