Jay Leno, upbeat and 12 pounds thinner (from daily runs), previewed his new NBC primetime show for the Television Critics Association tour on Wednesday.

“It’ll be more intense. There’ll be a lot more comedy in the show. It won’t be a talk show. It won’t be a variety show with wigs and hats.”

Some particulars:

• One celebrity guest, perhaps two at most.
• Musical acts twice a week, some Grammy-style collaborations.
• Bigger set.
• No desk (except possibly for the “headlines” segment).
• Reports from correspondents D.L. Hughley, Racheal Harris and Mikey Day.
• Occasional comedy bits from NBC News anchor Brian Williams.
• Celebrity car races (Shaquille O’Neal vs, Cameron Diaz) on track built next to studio.
• Signature comedy bits to end the show, leading directly (no commercials) into the 11 p.m. news.