As an example, searching for the "I Have a Dream" speech will return a Google Video clip of the speech itself, just below the text of the speech.
Google is also adding contextual navigation links (like Ask.com) to let users drill down to a particular type of information like "books" or "blogs."In addition, Google is adding a universal navigation bar across is home page and personal pages to make navigation easier and more consistent.
And there's Google Experimental. Go check it out.
Update: This is going live across Google's data centers throughout the day. So if you don't see the new features now, expect them before tomorrow.