Apple's yearly developer conference should see iOS 8, OS X 10.10, and likely some hardware.
Tim Cook Speaking at Goldman Sachs Conference Tomorrow, Apple Providing Live Audio Stream
Cook is unlikely to make any product announcements during the session, but he should offer some insight into Apple and its business. As a result, Apple is providing a live stream of the session to provide public disclosure of any statements he might make that could influence trading in the company's stock.
The session begins at 10:15 AM Eastern / 7:15 AM Pacific tomorrow.