The Swiss organisation has nominated 21 monuments for the 7 spots:

• Acropolis, Athens, Greece
• Alhambra, Granada, Spain
• Angkor, Cambodia
• Chichen Itza, Yucatan, Mexico
• Christ Redeemer, Rio de Janeiro, Brazil
• Colosseum, Rome, Italy
• Easter Island Statues, Chile
• Eiffel Tower, Paris, France
• Great Wall, China
• Hagia Sophia, Istanbul, Turkey
• Kyomizu Temple, Kyoto, Japan
• Kremlin, Moscow, Russia
• Machu Picchu, Peru
• Neuschwanstein Castle, Füssen, Germany
• Petra, Jordan
• Pyramids of Giza, Egypt
• Statue of Liberty, New York, USA
• Stonehenge, Amesbury, United Kingdom
• Sydney Opera House, Australia
• Taj Mahal, Agra, India
• Timbuktu, Mali

This selection was obviously politically and commercially inspired: each big/powerful country has one candidate even when it has nothing that's quite up to par (like Germany and Japan), each continent has at least one (even Australia), and of each country the most iconic monument was chosen. Still, that makes for a very balanced and interesting selection of what the world has to offer, so well done I say. The poll to determine the seven new wonders will be little more than a chauvinistic contest between the big countries, so it's this larger list that matters imo. I've visited 9 of these 21 nominees (Acropolis, Chichen Itza, Colosseum, Eiffel Tower, Hagia Sophia, Kremlin, Petra, Pyramids, Taj Mahal), how about you?

My personal Seven Wonders of the World would be:

1. Pyramids of Giza, Egypt
2. Hagia Sophia, Istanbul, Turkey
3. Taj Mahal, Agra, India
4. Temple of Karnak, Luxor, Egypt
5. Acropolis, Athens, Greece
6. Burj Al Arab, Dubai
7. Eiffel Tower, Paris, France
   

The single criterion for me is how awestruck I was (or think I would be) when seeing these monuments - we're talking about wonders here after all - and that is determined by their age, their size, their beauty and the technical achievement they were for their time.

Nothing beats the Pyramids when it comes to inducing awe - if you can grasp just how ancient and big they are. The Hagia Sophia is the most beautiful building I've seen - on the inside - and its dome was an amazing engineering feat for its time. The Taj makes the top 3 on its sheer beauty alone - it is the most beautiful and perfect monument I've seen. The Temple of Karnak is almost as ancient and impressive as the Pyramids. The Acropolis breathes the greatness of ancient Greek culture. The Burj Al Arab is the most poetic skyscraper there is, and at 310m among the taller ones as well. The Eiffel Tower is a fantastic structure and was the first building to be higher than the Greater Pyramid - immediately doubling its height. I also wanted to squeeze the Statue of Liberty in, but I'd have to see it before I could remove any of these 7.

Petra is the most beautiful place I've ever seen, but that's mostly for its natural canyons, so I don't know why it was even nominated for this list - its monuments aren't thát special. Machu Picchu seems to be a similar case (but I haven't been there).

I love making lists btw, in case that wasn't obvious yet :)