I would really like to have a kind of feature for autocompleting genres. One thing that would be even better is if you can create an easy text file where you put all the genres you like and you listen to. The content of this file could be like this:
---
Rock
Alternative
Indie
Trance
Trip Hop
---
The file could be named 'genrelist.txt' or something like that. You should always be able to update that file, to keep all your genres organized. A bonus feature could be that Winamp automatically keeps the genres in alphabetical order.
