They're calling it 2012 TC4, although I think they should give them names like they do hurricanes. Much easier to remember. And they've been watching this little asteroid for about two months.

Apparently, TC4 is just doing a fly-by, and is of no concern as far as hitting the earth. At least not tomorrow. But it will fly between the earth and moon. Close enough to have NASA keeping an eye one it.

You can read more about TC4 here.