[Conor Ryan]

Each one of the Shuttles built are engineering feats, reusuable spacecraft capable of taking large payloads as well as large (by comparison) crews into space. I just find it amazing that they are bringing it back into space.

Anyway I was reading up on the improvements they have made to the shuttle and its launching systems. I thought it was pretty cool, heres a list:
-A new Foam Clad Fuel Tank, the original tank damaged Columbia
-Sensors on the Wings to Detect Debris Impact during flight
-A new attachment to the Payloadbay arm, that will scan for more damage to the shuttle "skin" it uses Lasers and High Resolution Camera to scan for it, pretty nifty.
-Also they are testing fabric blankets, chemical washes, and mechanical braces. All 3 of those are going to be used to make repairs done while in space easier and better.
-A digital camera was also installed on the belly of the shuttle to take images while of the craft during lift off. (correct me if i'm wrong, i think it used to have a standard 35mm camera.)(no i don't know how i know that)

i'm sure there are many more upgrades, many of them safety related. I think this may be one of the safest launches of all time, it's just been awhile since one has happened.