I think Upman's theory is that if he hasn't got anything to say, he doesn't say anything. So the inference should be if nothing is said, then there is no new information of relative importance.
I'm of mixed thought on that. On one hand that makes sense. But on the other, I get that "warm/fuzzy" feeling when updates are posted, even if it's "We are still working on it, nothing really new to report, but just wanted to keep you advised". Probably more reassurance that "whatever" hasn't been shuffled off to the back burner or even off the stove.