Stumbleupon slipped out a new interface feature during the last 24 hours, and whilst I wouldn't regard it as ground breaking, it is actually useful, though they could have made it a little better.

My Shares

The My Shares feature is hidden in your inbox

Clicking through reveals a history of messages you have previously received through the "Send To" interface on the toolbar. If you haven't yet viewed items that have been sent to you, they won't be shown on this page.