285147 google seach poblems

i have a site listed #1 in google under the keyword adult business however when i go to those result and try to click on my site it brings user to some google page saying " This site may harm your computer." then when i click the link it wsill NOT go to my site... Anybody have any idea WTF this is and how i can fix it ? i see the same thing for 1000s of other sites so i assume its something new google has integrated