Kind of a boring, almost unpleasant Saturday. Lots of two-word phrases, like NICEWORK (16A: "Good going!"), UPNEXT (17A: Words before many a commercial), GOTAHEAD (58A: Succeeded), IMEANT (59: "ER … uh …"), and RECKONSO (58A: "Sounds about right"), among countless (ok, maybe there were fifteen or so more) others. We didn't know a lot of them right off - how could you, almost - but they were guessable with a cross or two. Boring.
I wanted BUMS immediately for "18D: They're often seeking change" (decent clue), but was a little surprised they actually went there. Also surprised, and annoyed, by THEWOMB (27D: Life starts in it). Seems almost political, and couldn't a case be made to say that both sperm and egg are "alive" before they get together? "It all depends on what your definition of 'is' is," right? … Blah.
Favorite clue/answer - SAM (39A: Merrie Melodies sheepdog), which Frannie got immediately. Pop Quiz - What was Wile E. Coyote's name?
I guess all I'm going to do is BLEAT and give more YOWLS, so I'll close now. I hope you enjoyed it more than we did.