I didn't catch the theme until I was done, even after getting ITSABOUTNOTHING (61A: Why this puzzle is like "Seinfeld"?). I was too busy filling in answers to even notice the circles. Now that I'm looking it over, however, I like it just fine. Two nice fifteens running through, and pretty decent theme answers. I even remembered TRINILOPEZ (23A: Singer with the 1963 hit "If I had a Hammer") with only a couple crosses! It's only a V short of a pangram, but I give Ms. Lempel extra credit for not trying to cram one in.
Some nice fill - SQUIRMY (3D: Having ants in one's pants) (fun!), PEZ (5D: Dispenser candy) (also fun), DANUBE (59D: Vienna's river) (always lovely to think about), and LACONIC (46D: Terse) (a nice ten-cent word!). I'm less fond of TINMINE (11D: Source of a metal once used for foil) and SESTETS (12D: Ensembles for six), but they're fine, really. Just a little odd.
It's a decent Monday.