The 'StackExchange' dropdown with the 'Inbox' tab at the top of the page is quite useful. However, I jump around from meta SO, to SO, to Programmers, to meta Programmers, etc. It would be helpful to sort these inbox items by StackExchange sites. Would it be possible to have the dropdown further refined by individual site, or at least sorting by site rather than just chronologically?
The inbox is meant for "your latest responses", and thus will always be sorted by time.
If you're interested in a per-site view on your responses, go to that site and your "Responses" tab in your profile.