The Ares I-X rocket has been delayed till tomorrow according to NASA.

Liftoff of the Ares I-X flight test vehicle now is targeted for Wednesday, Oct. 28 at 8 a.m., the beginning of a four-hour launch window. Join us right here for NASA's Launch Blog starting at 5 a.m. for the latest information from the countdown. Weather for Wednesday is better, but not great, with a 40 percent chance of weather violating launch commit criteria. Today's chance of violation was listed at 60 percent.

Earlier today it was an issue of a ship being in the way of falling debris.

Supposedly you will be able to watch NASA TV for the Ares Rocket Launch Live:

http://www.nasa.gov/multimedia/nasatv/index.html

Source...

If you haven't kept up with the Ares I-X rocket. Check out the information on the new rocket below:

NASA's first flight test for the agency's next-generation spacecraft and launch vehicle system, called Ares I-X, will bring NASA one step closer to its exploration goals. The flight test will provide NASA with an early opportunity to test and prove flight characteristics, hardware, facilities and ground operations associated with the Ares I.

Source
Press Kit
Fact Sheet

For those that don't like to read... Here's some videos on the rocket: