I am using Nexus S Android v2.3.4 with rooted stock rom.
What I am curious about is why Sneak Peek on my Nexus S trigger not the front camera but the back with double shutter sounds. For I have tested Sneak Peek on my Galaxy Tab 10.1 3G as well which shoot its front without any sound. All the results can be checked through web like the image below. Peek image is just black square with back camera as long as Nexus S laid down face upward. Again the clear and loud double shutter sounds have no sneak at all.
I am not quite sure whether this is on my own bug or something common problem with others too.
If any Nexus S user who installed Norton Anti-Theft Add-in test it from https://antitheft.norton.com and share results on my issue, it would be much appreciated.