.

Just a few of the changes made to Endeavour (first flown in 1992)

-Flatscreen LCDs replacing many gages and old CRT monitors
-New GPS computers allowing it to land a almost any large airport, instead of the limited number of airstrips its cleared for in the US
-New power systems allowing it to stay docked to the ISS for up to 12 days (50% more then it could before)
-New engine sensors that could help avert another disaster on takeoff
-150 miles of wire thats been inspected
-14 thousand safety checks that have have been completed

Read more about it here
http://www.flatoday.com/apps/pbcs.dll/article?AID=/20070807/NEWS02/708070347