A heads-up on something new in Amarok SVN (and coming in 2.2 for those of you not living on the bleeding edge):
We've had various bug reports over the years relating to character sets and collation, causing issues with matching searches for music or mis-sorted items. Well, hopefully no longer.
When you update to 2.2 (recent SVN users, see the note at the end of this post), your Amarok database and tables will be converted to use the 'utf8' character set and 'utf8_unicode_ci' collation as default for any table or column created from this point on. Every single text/varchar field will also be converted through a two-step process to use 'utf8' as the character set (the data inside was always UTF-8, but there was a possible mismatch between what the data was and what the database thought it was, if your mysql wasn't built to use 'utf8' by default). In addition, the character set used when talking to the embedded server (the protocol in the socket) will be 'utf8'.
Fixing this mismatch between what the server might have been using for character set/collation and the data we're putting in there should hopefully ensure that sorting and tags work very well for our users with some files wth non-Latin1 tags (probably just about everybody these days).
* Recent SVN users: if your build date is earlier than this post I'd recommend wiping your mysqle directory (not just a full rescan), as the initial commit of the updating code contained a bug that could possibly cause trouble down the line with user playlists...but you bleeding edge users should be expecting database wipes every now and then