Just because I can. Using Doug Adams’ mySpins, which aggregates play counts from your iTunes library:
The first column is the number of plays by artist – you’ll note that I set the artist for classical music to the composer’s name, as it’s easier to navigate on iPods with the tag set this way. The Grateful Dead is in the lead, followed by Franz Schubert, notably because I listen to his lieder a lot; these are songs that are, on average, 3-5 minutes each. There’s much less Beethoven, because those are longer works: piano sonatas, string quartets, etc. Bill Evans beats out Brad Mehldau by a bit, in part because I’ve been listening to him longer. And Bob Dylan is very high up, as I have all of his albums, and listen to them regularly.
The second column is the songs I’ve played most, across albums (that’s what “pooled” means). In other words, I’ve listened to Playing in the Band, by the Grateful Dead, 152 times, over 57 different albums (lots of different live versions). All of the top ten pooled spins are by the Grateful Dead.
Note that these play counts are not absolute for all artists or songs, as removing then re-adding music deletes their play counts. I’ve done that several times with certain composers, and with many Grateful Dead concerts.