The playlist... how I hate it, in the old sense of the term.
[Here we enter the "irritating story of the Good Old Days that you hear from your ancestors" mode...]
In the Good Old Days of radio, disc jockeys (actual humans with real-time control over what went out over the air!) could play just about anything, subject to FCC restrictions on language of course. You could actually call and they'd play what you requested--or perhaps, as happened to me a few times, they'd say "we've been playing that a lot; how about this instead?" The high point was in the late 60s and early 70s, but even as late as the early 90s I had the joy of hearing "O Fortuna" from Orff's setting of Carmina Burana followed by a David Sylvian track. (Alas, the station was sold after the flood of '93 and underwent the Inverse Midas transformation.)
Then came the playlist. A fixed list that was all that the station would play, until the next version of the playlist came out. For a while, you could request something--if it was on the playlist. Then the disc jockey would listen to but ignore your request. Now, more and more stations are remotely controlled, with the occasional local advertisement to trick you into thinking there's a human present. Just one more reason that American commercial music radio is the real "vast wasteland" of Newton Minow's famous phrase.
That was the old playlist, and its inventor merits a particularly incendiary portion of hell.
Fortunately, now playlists are often things under your own control, for your MP3/AAC/Ogg Vorbis/etc. player, or for your webpage via playlist.com. I've been adding to my playlist lately, and I hope you'll check it out.
I'm not totally about melancholy; I added some of the delightful songs of early Oingo Boingo (if only I could find "Capitalism" on playlist.com), Cream's ecstatic "I Feel Free", and Rasputina's "Bad Moon Rising". (Please, Rasputina, come play in Caledon. They'd love you!)
I also added what I could of Big Daddy's 50s and 60s restylings of later pop and rock music. Clever choices and arrangements, impeccably played.
But I will confess to be mostly about melancholy when it comes to music. It's a joy to put Pearls Before Swine's "Another Time" back on my playlist (and to add their "Translucent Carriages"), and don't miss Dave Mason's "Sad and Deep as You" or Heart's gems, "Dog and Butterfly" and "Dream of the Archer".
...which just goes to show that you should ignore the catsup: Carly Simon was right. "So stay right here, 'cause these are the good old days."