This the worst kind of dialogue box. Every attempt to use it involves a wasted click. Let's say I just want to add it to my "_Tops" playlist, that I'm using as a pathetic kludge until they add a star button. If it showed the first playlist in the selector, I could just click Save and be done with this. Instead, I have to click, select the playlist, and then click save. Everytime. Waste of clicks. Waste of time. Annoying.
Amazon Cloud Player
Number of Clicks to Add to Playlist: 5
Number of Clicks to Add to Playlist: 5
1. Click Song
2. Click Add to Playlist
3. Click select playlist
4. Click playlist name
5. Click Save
Google Music Beta
Number of Clicks to Add to Playlist: 2
1. Click Select Song
- Drop down menus to playlist
2. Click playlist name
iTunes
Number of Clicks to Add to Playlist: 2
1. Select Song
2. Drag and drop to playlist
Disclaimer: Okay. I see it now. They have another add playlist button along the top of the song list that uses drop downs. But when you click on the song, that one doesn't have the drop downs. Google seems simpler, but that's only because they're only working through song at at time, not having reached the multiple select stage of complexity.