[The Geek]

The privacy argument is kind of moot when you consider that anyone that did click install and posted in the thread will easily be identified by the author - thus allowing them to spam, exploit, or whatever.
So to protect yourself it seems like we should never click install and never don't post in the thread!

My final point being - if you need to keep your download a secret: don't download it! There are always going to be tripes that abuse things. However you can't line the world in bubble wrap just in case someone falls down (though a world lined in bubble wrap would be a hoot).
Ban the buggers that don't follow the rules. If it's a blatant spam using the notification email system - ban them for 2 weeks (or whatever).

That is how you ultimately prevent people from taking the piss.