The pros: Dinosaurs in Their Time is pretty cool. The years of renovation were worth it - the former dinosaur hall is completely transformed. Remember how everything was in straight lines and the dinosaurs were up on their big pedestals? Now the exhibit is sort of S-shaped, the walls are painted with colorful murals, the support columns are disguised as trees, there are plants around the dinosaurs and dead leaves underneath. Underneath every dinosaur is a nameplate with a lot of information and a touchscreen with even MORE information, including a section on how the Carnegie Museum researchers contributed to the discovery or naming of this dinosaur. There is a lot more natural light than I remember, and there are 2 balconies that overlook the exhibits for more photo opportunities. There is also an extensive timeline of the Carnegie Museum's expeditions and contributions to paleontology, and a timelapse video of the renovations.
The cons: The rest of the history museum is pretty lame compared to this new and awesome exhibit. The biggest examples are the 2nd floor Halls of African and North American Wildlife and the 3rd floor Birds hall. Big cases of taxidermy in a wood-paneled room with dim lighting - hardly thrilling. The 3rd floor Polar World is starting to look dated too. Even the fonts used date the exhibits.
Admission is now $15 for adults, $11 for students (free for Pitt students!). This does get you into the Carnegie Museum of Art also, but I'm usually tired after doing the whole history museum so I never get over to the art side. I would recommend seeing the dinosaurs, then skipping the rest of the history museum if you've been there before. The Dinosaurs in Their Time would get five stars on its own, but the rest of the museum is lagging behind unfortunately.