Most bodybuilders that you see will have a big strong upper body, but a smaller, disproportionate lower body. Lower body muscles are probably the second hardest muscle to work, second only to abs. A strong lower body is very important though. It's the foundation on which you build your strong upper body.
Those who do physical labor for their daily job generally have a naturally build lower body. Lifting objects and moving around on your feet all day constantly tax the lower body muscles, causing them to grow. I salute those who hold jobs which require large amounts of physical labor (construction workers, the military, etc). Sure, I'm a computer guy and my job generally requires that I sit on my ass all day in front of the computer. Not very healthy for lower body muscles. However, I don't see this as a misfortune, but rather as one of many challenges I must face.
I had another thought today with regards to lower body exercises. Those who actually do work their lower body on a regular basis probably don't see the gains they'd expect because the muscles are so tight. The muscles can't grow if they are not relaxed enough to stretch. With this in mind, I'm going to start doing 20 minutes of yoga and stretching twice a day, morning and evening, concentrating on lower body and hip stretches.
As promised, here is the second workout in my new routine. You'll notice there are a lot of lower body exercises. While doing exercises, it's extremely important that you keep perfect form through each rep. If the weight feels too easy, then slow down each rep and keep perfect form. If after a whole set of going slow they still feel light, then, and only then, increase the weight.