To Microsoft: If you implement this feature, I beg that you make it an optional setting. I hate this behavior, and a lot of email apps do it. I am selective about which emails I want to -- or have time to -- engage with at any given time. If I delete an email after reading it, I want to go back to the list and choose what I have the time or interest to read next. I may not want to read the next one.
Minor correction to my previous comment, it should have read:
"The other showstopper for me is related, the ability to put an email in multiple folders (or have more than one label)."
This missing feature is the primary reason I don't use Outlook (as much as I want to!), because I can't tell which emails have been tagged appropriately. The other showstopper for me is related, the ability to put an email in multiple files (or have more than one tag). If these two features were in Outlook, I would switch to it in a heartbeat, but for now I have to stick with the Gmail app. (I also like the way Gmail segregates email between Primary, Social and Promotions, and would love that carried over into Outlook, but that's not a showstopper.)