Adele's critically acclaimed new CD '21' is taking music critics and fans by storm; it currently ranks as the number-one album in the country, courtesy of Billboard's Top 200 Albums chart.

Now, it appears that the English singer-songwriter has made a fan out of John Legend, as well.

The Grammy-winning R&B superstar recently covered a track of Adele's single 'Rolling in the Deep,' which he performed a capella (beautifully, we might add).

Is it too much to ask for a John Legend-Adele duet in the not-so-distant future?

Hear the song below, then voice your opinion: Who sings the song better -- Adele or John Legend?