sure there is. lose the optical drive. redesign the innards. here just a small example:
asus U35 Weight & dimensions
Weight 1900 g
Depth 233 mm
Width 322 mm
Height (front) 14.8 mm
Height (rear) 24.6 mm
battery 11.5hr
video 310
MBP13
Height: 0.95 inch (2.41 cm)
Width: 12.78 inches (32.5 cm)
Depth: 8.94 inches (22.7 cm)
Weight: 4.5 pounds (2.04 kg)
battery 10.0hr
video 320
so the MBP is heavier, thicker, nearly as wide and has a (suggested) lesser battery time, and still they manage to fit an i5 ánd a dedicated GPU in the asus (although the 310 wont win many gaming awards).
the no room card has been played too often, just because SJ suggested it doesn't make it true neccesarily.