We still need to front-fill the wall with topsoil and seed it. Come springtime we'll re-check and adjust for level on the wall, then add a row of cap stones and either fill with another couple inches of gravel or some cobbles.
We found after it was built that my level base wasn't quite. The wall lost about 2" in the 35-foot run; I'm calling that close enough for gummint work.
And a word to the wise: those home-improvement shows that say this kind of thing is a weekend project? They're lying to you. Digging the trench and getting the sand base level took me the better part of two days of work in our rocky sticky soil. Laying the first course and getting it level and even was another 5-6 hours, and the rest of the wall took another 4 hours.
And I love Advil.
(Just for reference, each block is 27lb, and gravel is about 3,000lb/yd.)