Index: wp-admin/includes/class-wp-filesystem-direct.php
===================================================================
--- wp-admin/includes/class-wp-filesystem-direct.php	(revision 7736)
+++ wp-admin/includes/class-wp-filesystem-direct.php	(working copy)
@@ -47,7 +47,7 @@
 		if( ! $this->is_dir($file) )
 			return @chgrp($file,$group);
 		//Is a directory, and we want recursive
-		$file = trailingshashit($file);
+		$file = trailingslashit($file);
 		$filelist = $this->dirlist($file);
 		foreach($filelist as $filename)
 			$this->chgrp($file . $filename, $group, $recursive);
@@ -64,7 +64,7 @@
 		if( ! $this->is_dir($file) )
 			return @chmod($file,$mode);
 		//Is a directory, and we want recursive
-		$file = trailingshashit($file);
+		$file = trailingslashit($file);
 		$filelist = $this->dirlist($file);
 		foreach($filelist as $filename)
 			$this->chmod($file . $filename, $mode, $recursive);
@@ -177,7 +177,7 @@
 	}
 
 	function copy($source,$destination,$overwrite=false){
-		if( $overwrite && $this->exists($destination) )
+		if( ! $overwrite && $this->exists($destination) )
 			return false;
 		return copy($source,$destination);
 	}