For those of you out there using Internet Explorer 7, there's a fix so you can use the "Add media" menus in the administration panel of WordPress 2.5 properly.
There's 2 steps to be taken:
In wp-admin/includes/media.php, at line 817, delete the comma after false:
debug: false,
and, in wp-includes/js/swfupload/handlers.js, at line 99, delete the comma right after 36:
.animate({minHeight:0,height:36,},
That's it!