Now, the 25-year-old Memphis-bred singer is gearing up for the Sept. 12 release of his second solo disc, "FutureSex/LoveSounds," one of the most anticipated pop albums of 2006. And he's in the midst of an intimate club tour heralding its arrival with a stripped-down show designed to prove he's the real deal: a serious blue-eyed soul man who can carry the day with charisma and a voice free of sonic enhancement -- well, except for all that echo and reverb heaped upon the occasional high-register trilling.

From his grammar school days as a second generation Mouseketeer to the Lou Pearlman-engineered master class of 'N Sync's career (56 million albums sold!), JT has learned well how to give the people what they want, and he may be the hardest-working man in show business today, in more ways than one. He not only emulates the classic R&B showmanship of James Brown -- and Michael Jackson and Prince and Stevie Wonder and others too numerous to mention -- he's determined to pull out all the stops to win the hearts and minds of anyone with a pulse, an iPod or a CD player.

And damn if it ain't impossible not to love him for it, though not necessarily to the extent of the screaming, swooning, lustful fans -- 80 percent female, 20 percent male and now all of drinking age -- who packed the House of Blues on Tuesday night.

Fronting an absurdly tight 11-piece band -- including three backing vocalists, two keyboardists, two guitarists, a drummer and a percussionist, seasoned R&B pros one and all -- JT gave us 90 minutes of playground-rhyming hip-hop seductions (the new single "SexyBack"), sensual slow grooves ("Take It From Here"), hot 'n' horny aerobics workouts ("Rock Your Body"), Madonna-esque dance-pop ("Like I Love You") and lighters-in-the-air, hair-metal-inflected power balladry ("What Goes Around").

In the course of it all, the group threw in snippet after snippet of other well-known tunes -- from Nirvana's "Smells Like Teen Spirit," to "Summer Breeze" by Seals & Crofts, to the Eurhythmics' "Sweet Dreams (Are Made of This)" -- ostensibly with the goal of providing something for everyone, but also underscoring the more subtle message that any way you cut it, Timberlake is a pop star for the ages.

Not that JT took anything for granted. He dressed for success as a combination of 1940s swell and 1930s gangster -- think Frank Sinatra in that famous mug shot -- with a fedora, vest, tie and Oxford shirt that were each "casually" removed at selected points in the show for maximum "ooh and ahh" effect.

He flirted with the ladies -- and possibly the fellas -- intimating that he'd be glad to meet them at the bar after the show. (They all know he's still hot and heavy with actress Cameron Diaz but, hey, his grandma did recently tell a gossip columnist that marriage is "about how mature you are ... and he isn't ready.")

He worked up a serious sweat as he danced, popping and locking, slickly gliding across the stage and naughtily shaking his rump. He mimicked Wonder and Ray Charles while sitting at a Fender Rhodes electric piano; he strummed a Spanish rhythm on an acoustic guitar, and he gleefully beat-boxed on the microphone. And all the while, he soared from bedroom baritone to orgasmic falsetto, working a voice that, on close examination, really isn't that special, though he tries to wring the most out of every note and generally succeeds when he doesn't extend his four-minute pop tunes into eight-minute jams.

Is Justin Timberlake the new King of Pop? If he's smart, he'll realize that Jackson has soiled that appellation past the point where anyone should ever claim it again. But as long as JT keeps working this hard -- and he stays away from the amusement parks and the chimpanzees -- he's really got no competition.

jimdero@jimdero.com