Smartphone Hackers?

on msnbc.com, i read an article about experimenting people putting smartphones near their computer and the smartphone can be sending your every keystrokes to a hacker.. what?? So students at Georgia Tech's School tried this experiment. They first tried it on the iphone3GS to see if the other side can recieve the vibrations and try to figure out what the person was typing. But it was very faint. So they tried it with the iphone4 and it had much better signal wth the vibrations from the computer. So i guess hackers can use smartphones and decipher what you are typing on your computer.