Careful.
The media are jumping the gun a bit. This needs more study.
Actual document here.
Some questions:
Why would this report be any more infallible than the earlier ones that said the opposite?
Why would Iran suddenly decide in 2003 on their own that they would rather not be pushing a nuclear program? Think about it.
If Iran did have a weapons program as recently as 2003, isn't their protest that all they're interested in is generating electricity starting to look a bit thin?
An NIE like this doesn't get declassified to any extent unless the administration wants it. Why now?