Quick comment on ignoring interfaces from Discovery. We currently are not monitoring certain interfaces like "null" and "loopback" from our 500+ devices in NPM. I can imagine when we install V10 into production that every Node will be listed with these *New interfaces discovered. Not being able to Ignore interfaces by type or not being able to group them is going to be a lot of clicking in the web interface initially.
The Network Sonar does discover the null and loopback interfaces... after the discovery it give you a chance to choose with interface types to import. You can unselect loopback and I think the null come up as another type which you can also choose to not select for import.