"Earth's rotation rate is still slowing down -- our days are getting longer and longer. Eventually, our planet's tidal bulges will be assemble along that imaginary line running through the centers of both Earth and the Moon, and our planetary rotational change will pretty much cease. Earth's day will be a month long. When this happens, billions of years from now, the terrestrial month will be longer -- about 40 of our current days -- because during all this time the Moon will continue moving away.

In this future picture, any lunar colonists would then henceforth see just one face of Earth. You can imagine this setup by stretching your arm out and looking at your palm. Now twirl around. You're face and your palm stare at each other the whole time. If the United States happens to be on the back of your head, well, just think what people there do not see."
Garnered from this site

Jim