Fake or Real Comments

How can you tell if a comment is genuine or fake/spam?

I’ve had a couple now that although complimentary, mention vising my site previously which couldn’t be true as its new, some put links to their own/other websites in and most like this are in broken English which doesn’t automatically mean anything but adds to my suspicion of their authenticity. Should I be approving these comments or not?

The page I need help with: [log in to see the link]