Port and core LOX fill and drain valves are not showing closed after being commanded to close in preparation for launch. They're troubleshooting now; my educated guess is that they will miss the launch window for today and have to try again tomorrow or later.
This is a test launch of the new orion crew vehicle. Kind of an Apollo capsule on mild steroids. If successful, we won't be dependent on the Russians to ferry people to/from the ISS. And it will be the vehicle that goes back to the moon, possibly on to Mars.
And thank you for the ignorant antiobama comment, but this is a Bush era program to replace the shuttle.
This is REALLY exciting stuff. Really is a shame to see the space program today compared to what it was in the past. I grew up 20 minutes from the space center. My dad worked there and I got to see the shuttle up close and personal on several occasions and got to walk around the vehical assembly building (so massive it is almost incomprehensible) The building is so big that storm clouds have rolled in and it has rained inside!! My sister works at Space X. Really cool to see what they are doing.