and ID3 edition "IS ALLREADY IMPLEMENTED", i use the winamp in_mp3.dll for that, and works great.
we all know xmplay reads tags perfectly
There have been a few bug reports regarding differences between the handling of tags in XMPlay and the in_mp3/in_ogg dlls. Native tag editing would remove the need for in_mp3 and in_ogg (which are only used for tag editing), ensure that what you set as a tag is what XMPlay reads as a tag, and possibly remove confusion in tag editing (e.g. a dedicated "edit file details" menu item, as opposed to "plugin file info").
, so if you modify any file id3 tag, a right click in the updated file, and a menu option for updating tag info would work. or select the updated file, and press F5 for refreshing its info from Id3 tag is also a nice thing.
The way I see it is that any changes to the file details (by this I mean title/album/artist/tracknum), should update the file. The local database is only a cache because reading the details from every file is very inefficient, and requires all files to be accessible at the time. Having a 'local database' speeds up reading the file info, but the files themselves should be kept up to date with changes and be used should there be a difference between the cached data and the actual data. When you get down to it, most of the data contained in a .pls file is just cached (title, length) and overwritten by the actual file detials if there's a difference.