Young Justice is slated to air Fridays at 7pm (ET) on Cartoon Network beginning January 7th, 2011. Episode descriptions as follows below.

January 7th, 2010 at 7:00pm (ET)
Young Justice - "Independence Day (Part One)"
Justice League sidekicks Robin, Kid Flash, and Aqualad investigate a lab fire and end up finding a clone of Superman.

January 14th, 2010 at 7:00pm (ET)
Young Justice - "Fireworks (Independence Day, Part Two)"
Robin, Kid Flash and Aqualad rescue Superboy from Cadmus.

January 21st, 2010 at 7:00pm (ET)
Young Justice - "Welcome to Happy Harbor"
Young Justice mistakenly think the evil Mister Twister is actually Red Tornado "testing" them.

January 28th, 2010 at 7:00pm (ET)
Young Justice - "Drop Zone"
Young Justice's first official mission, and they don't even have a leader yet.

 The Young Justice episode scheduled to air Friday, February 4th, 2010 at 7:00pm (ET) is titled "Schooled."

Also I've posted a few creatures and character concepts of Young Justice, So scroll down to check them out:  
There will be more of these to come, so until then Merry Christmas!!  
 
 

Cool

Damnit, so we actually have to wait till the 21st for the new episodes

So Artemis is Green Arrow's niece 

Why is Grayson the youngest?

" So Artemis is Green Arrow's niece  "

" @Emperor Gonzo Noir said:

" So Artemis is Green Arrow's niece  "

They also list Miss Martian as J'onn's niece, so maybe this should be taken with a grain of salt. "

Someone's not follow lab protocol with them flip flops