If, like many people, you access your digital music collection in multiple ways, you may have come across the odd habit of iTunes to name some music files in its library with both the artist and track title in the name column when imported. When played, the song fixes itself and shows up with just the name. But, if you reimport the song... say when you add new music to the folder... it shows Artist - Track in the name field again until it is played. It will also transfer to your iPod in this same format... and playing it there won't fix the name.
The Cause: M3U Playlists
The cause is a simple one: M3U playlists. iTunes imports the playlists when you tell it to add music to your library. If a track is mentioned in the M3U playlist and the playlist includes the track's title information -- created by Winamp, for example -- that title will supersede the track's actual title in the MP3 tag until the track is played. When played, iTunes will read the MP3 tag from the track and label it correctly in the iTunes music library.
The Solution
The simplest solution would be to remove your M3U playlists. But, personally, I like having them with the albums so I can browse my library in Explorer and just double-click to play an album sometimes. So, if you wish to keep them, the solution is to edit the M3U file.
By default, Winamp (and many other MP3 players) adds the artist and title information to the M3Us it creates. The problem is, that it creates it using both the artist and title in a single field in the file:
#EXTINF:246,Artist Name - Track Title
iTunes will import that field as the actual track title when it imports M3Us. So, the solution is to edit your M3Us to remove this extra information. The original M3U looks like this:
#EXTM3U
#EXTINF:246,Artist Name - Track Title
01 - Track Title.Mp3
#EXTINF:210,Artist Name - Track Title
02 - Track Title.Mp3
...
Edit it using any text editor (Notepad is fine) and remove the extra details, ending up with this:
01 - Track Title.Mp3
02 - Track Title.Mp3
...
Additional Considerations
Although this will solve the issue, you do need to be concious of when you edit a playlist in an MP3 player like Winamp, as it will add the extra info back in, requiring you to manually remove it again. For those of us that only use playlists for whole albums, this isn't an issue. But it will be for others.