Note that I issued a revised version of this pattern on 2/11/12 that clarifies an oddly confusing bit of direction in the “Foot” section of the original pattern. It only pertains to those who are resizing the sock upward, so if you downloaded the pattern before 2/11/12 and are knitting as the pattern is written, this bit won’t be applicable to you and you should be fine with the original version. However, feel free to download the revised pattern if you’d like to have the most up-to-date version on hand.

Gauge for DK weight - 5.5 stitches/inch on US3/3.25mm
Gauge for Sport weight - 6.5 stitches/inch on US2/2.75mm or US2.5/3.00 mm