The opening song on "Wilco (The Album)" is a bright, poppy tune called "Wilco (The Song)." It's a greeting card to the band's fans, a promissory note: When you need us, we'll be there.

"Did someone stick a knife in your back? Are you being attacked?" frontman Jeff Tweedy sings. If so, Wilco has "a sonic shoulder for you to cry on ... Wilco will love you, baby."

If you think it's arrogant for a band to write a song about its emotional relationship with its fans, you aren't one of those fans to whom Wilco is writing. Or make that to whom Tweedy is writing.

Wilco (the band) is really Tweedy and whoever is playing behind him at the moment. Over the last 15 years and several versions of the band, its only constants have been himself and bassist John Stirratt. The current Wilco has been around for five years and is, arguably, the band at its best, particularly if you're talking about virtuosity and live performances. One viewing of the new documentary "Ashes of American Flags" ought to be ample proof of that.

During Wilco's 15 years, Tweedy and the band have risen steadily to that status where fans are so loyal and patient (and smitten) that longevity is as guaranteed as it can be in a music world that is quick to devour its young and dispose of its elders.

Neil Young lives in that place, too, where fans forgive the missteps, rationalize the mediocrity, fawn over (and sometimes exaggerate) the successes, new and old, and treat the live shows like revivals and reunions.

Tweedy hasn't cultivated Young's iconic legend, but he shares his affinity for taking risks and surprising his fans and his personae as a family man with a firm set of morals and manners. In a culture that rewards so much errant and juvenile conduct, Tweedy is resolutely a-behavioral. If he were a tennis star, he'd have been Pete Sampras, not John McEnroe.

He's also self-effacing, a trait that lurks within "Wilco (the Song)," one of 11 on the band's seventh studio album. The disc came out Tuesday, more than 14 years after "A.M," the debut that followed the breakup of Uncle Tupelo, the trad-country/punk band Tweedy formed with Jay Farrar near St. Louis in the early 1990s.

"Wilco (The Album)" is different from "Sky Blue Sky" (2007, the first studio album by the latest incarnation of Wilco) in several ways, but it is also like each of the six previous Wilco albums in ways both subtle and explicit. As on "Yankee Hotel" and its successor, "A Ghost Is Born," there are moments of dissonance and distortion, even in the middle of the poppy opening track, which also sounds sprung from the "Being There" sessions.

Other pop songs recall moments from "A.M.," "Summerteeth" and the first "Mermaid Avenue" album. The most conspicuous of those is "You and I," Tweedy's duet with singer/songwriter Feist, which sounds handcrafted for a TV commercial for diamonds, right around Valentine's Day.

It's a charming indie-rock-star collaboration: the teddy bear and the Barbie doll singing sweet nothings back and forth, though the song does have a point: Love needs mystique, some elbow room, some secrecy. "I don't want to know everything about you/ And you don't need to know that much about me ... "

Tweedy has been writing those kinds of bubbly ditties for years, all the way back to "No Sense in Loving You" on Uncle Tupelo's "Anodyne." They're not deep or provocative, but they require a knack, and he still has his.

That one's followed by another catchy, up-tempo song, "You Never Know," which jumps out of the gate on a beefy roadhouse piano riff and sustains its trot for more than four minutes. Tweedy is preaching: "C'mon children, you're acting like children/ Every generation thinks it's the end of the world ... "The verses are joined with a chorus - "I don't care anymore" - that's a frothy spray of Beatle-ish harmonies, and the results insinuate a cleaned-up, refined version of something like "I Got You (At the End of the Century)" from "Being There" or "War on War" from "Yankee Hotel."

As it did on "Sky Blue Sky," the band resembles a crack team of studio virtuosos - the kind that inhabited scores of albums in the 1970s. (That slide guitar on "A Sunny Feeling" sounds like Waddy Wachtel is sitting behind it.)

The song that best exemplifies this fusing and concocting bits of Wilco's varied past into something present is the murder anthem "Bull Black Nova." It opens with Tweedy singing over the rapid pulse of a piano note, the beat of a drum and the throb of a bass. The mood grows from anxious to alarming until an instrumental interlude that recalls Steely Dan circa "Aja" or fusion-jazz a la the Crusaders - the sound of the band baring its chops.

But "Nova" quickly returns to its ominous narrative and the music grows more dissonant and alarming and deranged and the mood explodes into a crescendo, a harrowing climax, and the singer is in despair, screaming: "I can't calm down, I can't think/ I keep calling/ There's blood in the trunk/ I can't calm down ... "

Then the music stops suddenly, as if severed, its last note fading - somewhat like the end to the Beatles' "A Day in the Life."

Like its album, the song "Bull Black Nova" manages to resemble something we've heard before, but not quite the same way. Something familiar has been revived, rebuilt and refreshed.

That seems to be the point or at least the effect of "Wilco (The Album)." It's a reassurance to fans and friends that although it may have fewer tricks and surprises up its sleeve, Wilco (the band) is still relevant, still focused, still evolving, still committed to being there.