Today is Martin Luther King Jr. Day, the day America honors the American Baptist minister and activist who became the most visible spokesperson and leader in the civil rights movement. Google honors Martin Luther King Jr. every year, it is an American holiday.
This year, Google has a Doodle depicting a "young girl perched on her father’s shoulders, enthralled by the power and eloquence of Dr. King’s words." It was designed in collaboration with the Black Googlers Network (BGN), one of the largest employee resource groups at Google.
You can learn more about the Google Doodle over here.
Bing also has a theme, as they do every year as well, theres is a slideshow from the day of the speech as well:
This image has been removed because of fear of being sued over copyright...
Here is last years set of logos.
Forum discussion at Google+.