Thanks, i have updated the script since i last posted as well. Fixing some bugs and adding highlighting for codeboxes namely.
Since scripts run at the domain level, they have access to cookies/history etc from the originating site.
So someone could potentially get access to your account.
But cross-site scripting isnt possible as far as i know, so running trusted scripts wont endanger you or your other sites.
But you should always check the script to see what it does anyways ;)
I don't know how secure greasemonkey is though.
Since scripts run at the domain level, they have access to cookies/history etc from the originating site.
So someone could potentially get access to your account.
But cross-site scripting isnt possible as far as i know, so running trusted scripts wont endanger you or your other sites.
But you should always check the script to see what it does anyways ;)