Each year, YouTube gets an influx of commencement ceremony addresses from universities across the United States as well as other videos from many graduates' big days. Last year, we reviewed some of the all-time most-popular speeches and took note of a rising trend for commencement day time-lapse videos.

Ellen DeGeneres' mock graduation ceremony for singer Justin Bieber has, naturally, drawn some of the most attention (with 2.5 million views), but right up there with the popstar is another most-watched video from the commencement season: an unexpected proposal on stage at American University.



Actors and politicians dominate the list of most-popular speeches so far from this year's ceremonies, with SNL's Andy Samberg and Glee's Jane Lynch atop our chart:

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