Karl-WEI have tried to use the New Outlook and there is no way it can be said to be nearly complete. The video mentions plenty of features that are still missing. Plus it doesn't support GMAIL with IMAP yet. There is a long way to go before this could be considered amazing and nearly complete.
From the other blog, here is the list of items there are not available yet, and this doesn't include items that have been requested but appear not to be planned (like follow-up flogs or tasks):
New Outlook for Windows capability | Status |
Multi-account | In development |
Offline | In development |
3rd party account support (Gmail, Yahoo!, iCloud and other IMAP accounts) | In development |
POP support | Investigating |
Support for accounts in US Government clouds | Planned |
Outlook data (.pst) files | Planned |
Search Folders | In development |
Folder reordering | Updated to: In development |
Programmability | In development: web add-ins |