Also don't overlook monitor calibration like Spyder Pro. That will help alot for color consistency and exposure adjustments.
+1 Before I purchased a Spyder Pro, I was seeing a huge difference between how pictures looked on various PC's and printed. This is an excellent investment.
This is my workflow for landscape pictures, similar to some of the other posters above.
1. adjust overall brightness level
2. adjust color temperature
3. adjust blacks and whites (use ALT key on a PC and left click on the slider, move until totally black)
4. adjust shadows and highlights depending on the picture
5. apply s-curve for contrast
6. apply color specific saturation depending on the picture
7. apply vibrance (normally 5 to 10, but as much as 20 for back-lit or cloudy day pictures)
8. apply clarity (normally 2-5)
9. reduce saturation (0 to -5)
10. Apply noise reduction for high ISO pictures, either globally (5-15) or using the paintbrush tool if in specific areas of the picture
11. apply lens and CA correction for lenses that need it (24-105 at wider aperatures, 15-85)
12. straighten and crop as needed
I typically do less post processing for portraits. Normally, I do not add vibrance or clarity and adjust shadows and highlights less.