Open != free.<p>Lack of openness: a browser plugin that is less stable and slower on Mac and Linux that noone else can fix except Adobe...and only if they choose to do so.<p>Lack of openness: a browser plugin that doesn't properly utilize cookies on non-IE browsers that noone else can fix except Adobe...and only if they choose to do so.<p>Lack of openness: a browser plugin that doesn't properly return HTTP status codes on OS X that noone else can fix except Adobe...and only if they choose to do so.