Today I checked on the raised beds. Most seem to be drying nicely, and are thawed down to the depth of a trowel. However, the beds I covered in black weedcloth still are frozen below about 3 inches. So this technique will not be used again! We are having a little cold snap, but temps are expected to moderate by the weekend, so I expect these beds will also thaw out soon (now that the cloth is removed).
I am a big believer in soil temperature governing when I plant. I see no point in sowing - even spring crops - "as soon as the ground can be worked" if the soil temp is too low. In my experience the seeds just sit there, and often rot. Even spring crops germinate faster and better in warmer soil.
So while it is frustrating to read about fellow gardeners getting the jump on me, I think it's prudent to wait awhile; at least until the soil reaches 50+ (F.).
And where are we now? Right at 40 (at mid-day). So there's still more waiting. But I should be able to till the beds this weekend, fertilize, and get everything ready.