I've just finished reading Rolling Thunder, John Varley's wonderful sequel to Red Thunder and Red Lightning, his ongoing series of tributes to the golden age of Heinlein's juvenile sf novels.
The Thunder and Lightning books are fantastic, action-packed, science-packed homages to Heinlein's best work, and Rolling Thunder is no exception. In this volume — set decades after the action concluded in Red Lightning — a descendant of the story's original heroes named Podkayne (due to a vogue among Mars residents to name their kids after fictional Martians) finds herself embroiled in several kinds of adventures, including a musical encounter with vast, unstoppable, deadly crystalline lifeforms; a military hitch; musical stardom, and more. She is at the center of the saga of the ongoing collapse of poor old Planet Earth, laid to waste by security paranoia, religious fervor, greed, and environmental catastrophe.
Through Poddy's eyes, we watch the action unfold on an interplanetary scale, re-visiting the best characters from the previous books (the stasis fields from Rolling Thunder are an effective means of indefinite life-support, so practically everyone is still alive and chumming about, as in Heinlein's Cat Who Walked Through Walls), and the action skips seamlessly from the micro-scale (Poddy's familial and romantic entanglements) to the macro (interplanetary war!).
I can't recommend this stuff too highly. Varley is clearly bent on reviving everything that made the Heinlein juvies great, and he's doing a hell of a job with it. These books are fond without being nostalgic, reverent without being old-fashioned. Everything about them is utterly contemporary, but it's easy to believe that Heinlein would have written them (more or less!) today.
See also:
Varley's Red Thunder qualifies for preliminary Nebula ballot
The novel Heinlein would have written about GW Bush's America