Hello. I updated to 10.6.7 yesterday. This morning, a small transparent window appeared on the top right of the screen saying that Growl-1.2.2 is available for update. With the MacDefender situation, it is better to be careful. From searching the internet, I found that it is kind of a notification system. I am not sure if the source of the program is reliable. Is it safe to install it? About every month, I receive notification that a new version of this software is available.