http://dsc.discovery.com/news/afp/20030127/teleport_print.html

The practical use of that technology is still too far away to truly spark my interest.

In fact it is a language abuse to speak of teleportation. It is only instant transmission of an information through twin particles that react in the same way.
By the way, I read a quite funny book called "The physics of Star Trek" a few years ago. It was trying to see if all the gadgets used in SF movies could be possible. About teleportation, even if the technology enabling to duplicate anything particle by particle was available, the main problem would be to have he information needed to rebuild whatever you want to teleport.
For example, the amount of information needed to make a complete "particle map" of a human being would be so huge that it would fit only on a hard drive bigger than the size of the solar system !

OK, so teleportation isn't possible by today's reality. There's always tomorrow, even should that tomorrow be way in the future. At the turn of the 20th Century, man hadn't flown yet, yet within 70 years, man had walked on the moon. By the end of this Century, who knows what may be reality? It would seem that the year 2003 will look as ancient and strange to those alive in 2103 as the year 1903 does to us.

Well, this argument is always given in that kind of discussion. I should look back at the book, but it seemed a quite radical impossibility, not due to present technology but to theorical reasons. Whatever technology used, the amount of information would always be too huge to manage.
I'll try to find the exact thing.

I was listening to an interview on NPR recently, (don't remember all the details) but it was with some professor of physics. He talked about the "old days" in his field and attempting to describe how matter came together, and how so much of that was complete guesswork after a point, until some new device was invented that allowed them to see much more, and challenge/verify what they'd expressed before. This professor also said that the Nobel Prize for this invention was one of the fastest ever granted. This is the style of breakthrough that will allow some of the fantasy part of science fiction lore actually come to be.

I found my book. Here is the reasoning
The human body conatains 10 exp 28 atoms. each atom requers a big amount of information (localisation energy level…). Let's imagine it is only 1K.
So we need 10exp28 K memory.
If we used 10Go harddrives to store this information, the stack of harddrives would have the length of 1/3rd of the galaxy !
And to get this data transmitted, 10 billion years would be necessary.

If we consider the rate of progress of computers (memory, speed…),
such a task could be possible in 300 years. Only the data part, of course, not the whole teleportation thing.

In fact, the very idea of teleportation (as described in Star Trek) implies that an object can be disassembled and assembled, atom by atom, like a lego model.
But the quantic theory has proven that this is impossible. The principle of Heisenberg makes it impossible to make an accurate "map" of anything particle by particle, because such a map would alter the composition of what is being observed. And this is not a question of technology, but a scientific impossibility.

my book is : "the physics of star trek", by Lawrence M Krauss, Basic Books, 1995.

If you took somebody apart particle by particle they would be dead when you reassembled them.