With an average of 5 planets per star (that's my conservative guess) half a trillion stars in our solar system, and an estimated 100 billion (KNOWN!) solar systems, we have 2.5*10^23 planets in the universe. This number will definitely continue to grow as our telescope technology improves. I would say that the odds of NONE being habitable are VERY small. It's kind of like trying to roll a dice a hundred times without hitting a '1.' You have to hit something eventually! Especially different types of life like microorganisms, which can survive in fierce environments. With so many planets, advanced life is very probable elsewhere. Problem is, the light emitted from Earth takes billions of light years to reach the further planets, so if they somehow saw us through a telescope, that activity will have been from billions of years ago. Life will be long since gone by that time.

Progress will be difficult, considering that the closest habitable planet is 25 lightyears away. If we can manage to send colonizers, we will probably never speak to them again, since any light-based communication will take 25 years to reach us. We will have to find a way to break the universal speed limit which is the speed of light if we want to overcome this obstacle. Still yet, relativity will hold for those who travel and we will age relatively faster and will be dead sooner than them. Once again, a problem for communication.

Of course they might figure out how to analyze spectral samples for signs of life (I remember hearing they did something like this recently), which would not require us to physically go there. But I do hope we find a way to physically go there!

 My Answer Is also Yes I believe we would be extremely arogant and nieve to say that we are the only intellegent life in the universe I have done lots of research and found many interesing things on the web. However its all written by humans who have a knack for lying so the only real answer remains to be seen and yes I am 33 and do believe proof will be found in my lifetime.

 Yes, life also exist in some other planet.Man can't imagine.God has created this universe we can't imagine how much living things exist in this universe.We can think according to our mind but God knows the truth.Science is searching to find the secrets.So it takes time to find out by man.

 Yes.I would like to think we aren't the only life form in the universe. It's a big place and scientists and astronomers still have a long way to go if they're going to declare every single planet uninhabited. Just wondering if there are some other beings thinking the same thing about us out there somewhere.

 Of course,scientists have found evidence on Mars.Don't think aliens are just coming around to look,progress has been made already.All you have to do is look up in the sky,someone just might be looking at us.

 This universe is too huge for us humans alone, and there may be many other life forms throughout the universe. But it all depends on how we define the life forms. We believe on carbon based oxigen breathing life forms based on water. But there can be other forms of life. If they come to us, they has to be surely intelligent than us. When they send a ship, while it is travelling, they would have developed thousand times more.
I say, Surely!

 Other than the stray parasite, bacteria and amoeba, I'd say the chances are slim as far as finding other humanoids or their variants. I'd personally like to know why is it that every photo taken of a UFO is always grainy and never an alien waving out of the window! HA

 Yes!Why not believe? You can not deny what you do not know. I can see people here continue exploring.

 If space is infinite, then logic suggests that there must be life out there.

 Actually the word ''LIFE'' implies to the fact the what we feel and what we see. well!! the Almighty Gods knows better but nevertheless what I think is that there do exists life there on other planets but we can't see them, similarly as they can't see us.

 Space knowledge has made many historical advances in my life time and everyone worries about little green men. I say it will give us one more color to learn to accept and see if we can control how they feel and think. After all are we not the perfect race?I hope there are little green men and they obviously are very intelligent because they never stay very long to visit.I believe it is possible after all look how long the legends of the mini horses floated through the Indians and every one thought they were crazy made up fables-they really did exist.