I just saw the revealer for this puzzle, and it made me laugh. In case you were wondering, it comes at 72A: [this space left intentionally blank] ([NOTHING]).
So the theme is phrases that start with the word "nothing," but with that word left out. For example, you get 20A: ... A matter worth considering ([NOTHING]TOSNEEZEAT). There are a total of ten theme answers, which is majorly impressive, especially when you notice that 18A, 20A, and 24A actually touch each other at 19D: Address starter (HTTP). Similarly, 52A, 57A, and 63A touch each other at 49D: Level (TRUE). The fact that the glue is kept to a minimum is very nice.
We also get ASBESTOS, ELBOWOUT, HANGSTEN, and DORISDAY, all fine down answers.
I enjoyed the following clues:
2D: "Little ____ in Slumberland" (early comic) (NEMO). There's actually a Genesis song about this from "And Then There Were Three".
29A: Whale's closest living land relative (HIPPO). I did not know that.
34A: They're taken in chess (TURNS). So literal.
... to turn my nose up at, so overall a definite win.