--- apply_replaygain.pl	2007-12-31 14:55:39.000000000 +0100
+++ apply_replaygain.pl.new	2011-01-05 18:31:38.112189683 +0100
@@ -43,7 +43,7 @@ use Getopt::Long;
 our $metaflaccmd = "metaflac";
 
 # Depending on your application, you may not require --preserve-modtime
-our @flacargs = qw ( --preserve-modtime --add-replay-gain );
+our @flacargs = qw ( --add-replay-gain );
 
 #-------------------- End User-changeable options ---------------------
 
@@ -66,7 +66,7 @@ GetOptions( \%Options,
 #$d_info     = 0;
 #$d_debug    = 0;
 
-showusage() unless ( scalar @ARGV <= 1 );
+showusage() if ( scalar @ARGV <= 0 );
 
 # Use current directory if no dir specified on command-line
 @ARGV = ('.') unless @ARGV;
@@ -147,7 +147,19 @@ sub process_dirs {
 }
 
 sub showusage {
-    print "Usage goes here\n";
+print "flacgain [options] [directory]
+    
+Options:
+    --processall        Default behaviour is if all files in the directory
+                        have ReplayGain information (specifically, the
+                        REPLAY_ALBUM_GAIN tag) then the directory is skipped.
+                        This option recalculates ReplayGain information
+                        for all directories.
+    --info              Output information (directories processed, etc.)
+    --debug             Output debugging information
+
+directory is the directory to scan for flac files. If omitted, the
+current directory is processed.\n";
     exit 1;
 }