With the upgrades, visitors now see the license plate from the truck that contained the bomb. One may now see the sign and the door from a hotel where Timothy McVeigh stayed along his path to OKC. You may hold your breath when you see and understand the implications of the shirt McVeigh wore upon his arrest, along with his Michigan driver's license, the citations issued for his traffic stop, the ear plugs that were in the passenger seat of the stolen car he drove, and the car itself. And that's not to mention the actual bomb fragments, the gavel used by the judge in McVeigh's sentencing trial, and many other real objects - all in addition to survivor and rescuer stories and artifacts.
The renovations at the museum include some amazing technology, as well, incorporated into the displays, video presentations, and a number of really well-presented, interactive touch screens.