I knew something didn't look right the first time around. Mainly, the stripe pattern, which had matched perfectly up until the heel, was suddenly waaay off. Instead of stopping to think what of what might be causing it, I spent my time pulling out lengths of yarn to "skip" and sew in later to keep the color pattern (mostly) correct. I probably had a yard and a half of loops inside the sock when I finished the heel and stopped to really look at it. Hmm... D'oh!
I then remembered that the first sock heel was done with 60% of the total stitches, instead of 50%. Brilliant.
So I ripped it out and tried again. I'm sure I don't have to tell you that the stripes are matching now.