I'd like to endorse vital's request for the option to create 1 playlist in the root folder for all the songs in the sub-folders. This would seem to be the logical next improvement of an already terrific app.
For example, I have my New Age music collection, approximately 1000 songs, in subfolders according to the artist name, 116 artists. If I drop the New Age folder onto the app it's going to create 116 m3u's in their respective folders, which is great - very useful.
But I'd also like to, as would vital & Xennon, be able to create one playlist in the root folder that has all 1000 songs. I do have a current m3u that has all those songs but I had to create it by copying each artist's songs into one big all-inclusive folder and then making the playlist. Having sPlaylistMaker do that would have been an elegant solution and saved a lot of time.