A female friend called me the other day and started the conversation by singing "Santa Baby."

My friend did a pretty good job singing. It made me smile. My friend had no way of knowing my affection for the Betty Boop-style vocals Madonna delivered on her version of the song (to which my friend was singing along), nor did she have any idea that "Santa Baby" is one of my favorite Christmas songs, one of my favorite Madonna songs, and a fairly important touchstone in following Madonna's many career arcs.

Context is everything.

One of the things ignored about Madonna is her sense of humor. Until recently, at least, she's always seemed capable of deflating herself by showing a comic side.

The first revelation came at Live Aid in 1985. Nude pictures of the singer had just appeared in Penthouse magazine.

As has been written in this spot before, unlike now, where a conveniently "lost" home videotape can lead to reams of publicity, at the time that Penthouse appeared, Madonna was courting a potential early end to her career. MTV was already regarded as evil by many authority figures. Certainly a naked pop star wasn't going to be tolerated.

Instead, she shrugged it off, refused to even take off her jacket in the sweltering Philadelphia heat and said, "I ain't taking (expletive) off today."

That's context - and humor - worth remembering.

A couple of years later, Madonna was an even bigger deal. The "True Blue" album produced four No. 1 singles (and a title track that should have been a No. 1, but peaked at No. 3).

In the midst of that mania came "A Very Special Christmas," which included Madonna's "Santa Baby."

Madonna had paid tribute to (or ripped off) Marilyn Monroe's "Diamonds Are a Girl's Best Friend" production number in her video for "Material Girl." Heck, she'd released a song called "Material Girl." What better way to show a little humor about the perception that she was being autobiographical than to record a cartoony Christmas song?

(And maybe along the way, Madonna was able to introduce a few people to the original recording by Eartha Kitt.)

Keep in mind, we're talking here about things that happened 20 to 25 years ago. Some of Madonna's chart contemporaries continue to share her ongoing success. Bon Jovi, Van Halen and U2 continue to be concert draws and have some artistic merit.

On the other hand, there's Whitney Houston, George Michael, M.C. Hammer and Bobby Brown, all of whom seemed poised for futures that consisted of something more than tabloid headlines.

That quartet of names should serve as a testament to Madonna's longevity. Twenty years ago, when a skeptical co-worker asked me if Madonna's music would survive, my response was, "I can't think of any reason it wouldn't. She records solid, memorable pop songs. There's nothing earth-shattering there (with the potential exception of the 'Like a Prayer' album), but it's good stuff."

And Madonna's best days as an artist are probably behind her. Her last truly significant artistic accomplishment was "Ray of Light," which came out in 1998. (And to her credit, still sounds current now.)

But subsequent releases have still been greeted with fanfare, and she packs concerts wherever she plays. Her 2004 tour and this year's series of shows were the top-grossing tours in the U.S.

This year, she surpassed Elvis Presley and now holds the Billboard charts record of 37 top-10 hits. She's the most successful female artist in history, and continues to reinvent herself and serve as an inspiration - for good or ill - to a number of female performers today, at age 50.

One of the exciting things about following The Beatles was their continual style changes. The group rarely repeated itself. But they didn't do it as long as Madonna has. It will be fascinating to see what kind of changes are in her future.

Maybe she'll turn into a cyborg. Unless she is already.

timcain@herald-review.com|421-6908