Compare the size: the old MacBook Pro on the left versus the next-generation MacBook Pro on the right. The new laptop is much thinner than the old one. Have a look.
These are the numbers, old vs new:
Height: 0.95 inches (2.41cm) vs 0.71 inches (1.8cm) Width: 14.35 inches (36.4cm) vs 14.13 inches (35.89cm) Depth: 9.82 inches (24.9cm) vs 9.73 inches (24.71cm) Weight: 5.6 pounds (2.56kg) vs 4.46 pounds (2.02kg)
And seven hours of battery? And 8GB? And 256GB SSD? And retina graphics? I can't wait to get my hands on it.