Most LCDs can be hard to see outdoors under summer sun.
Personally, I won't buy a camera without a viewfinder for a different reason - image stability. If you are using 2 hands and viewfinder, you have 3 points of support for your camera. But if you like using one hand to compose and shoot, viewfinder is not important.
Nikon D90, D80
Nikkor 16-85mm AF-S DX F/3.5-5.6G ED VR, Tamron SP AF 28-75mm F/2.8 XR Di LD Aspherical (IF) macro, Nikkor 50mm F/1.4D, Nikkor 50mm F/1.8D, Nikkor AF-S VR 70-300mm F/4.5-5.6G IF-ED, Sigma 105mm F/2.8 EX DG Macro ||| 2x SB800 | SB600 ||| Manfrotto 190XB