Any Joni Mitchell fan who went to last night's tribute concert at Carnegie Hall with the hope of studying her reactions to every song must have been disappointed by the first words from the stage -- a reading of a letter stating that she was skipping the event because of a "very sick cat." (No, she wasn't referring to my presence in the audience. I swear.) In a very Joni-ish way, her letter explained the precise details (cat was partially paralyzed, dragging back legs, needs spoon-fed medicine twice a day) -- which may seem odd to some of you, but made total sense to me. When my poor old German Shepherd was sick (dog was partially paralyzed, dragging back legs, needed medicine twice a day) -- would I have skipped a Carnegie Hall tribute? No way! But Joni always had a better sense of priorities than most people, and I'd argue that she was offering us a reality check.

In any case, the initial disappointment turned out to be a good thing. Without Joni in the balcony, we had no choice but to watch the performers and listen to the songs. That's when I understood the evening's big challenge. Joni's vocals are so distinct that it seems nearly impossible for anyone to get beyond her. As Tom Rush, Suzanne Vega, Amy Grant, and Richie Havens played, I felt as if I could hear her own version in the background. So I decided to keep track of anyone who sang so distinctly, or with such heart, that I could forget the composer for a minute. Here's the list:

Laurie Anderson, "Both Sides Now" (from Clouds): Plinking away at an odd sort of violin/mandolin hybrid, Anderson made this overplayed standard sound new again. Her squinted eyes opened and glared for just a second, as she sang "if you care, don't let them know," a brief glimpse of pain.

Martin Sexton, "Marcie" (from Song to a Seagull): It isn't easy for a guy to put new life into a very sad song about a woman scorned, but Sexton's got a terrific voice, hopping around on some new notes that recall Joni's style without copying it. (See his site.)

Jesse Malin, "Carey" (from Blue): Man, what a character. Young rocker Malin had a blast with his hyped-up, countrified rendition, then jumped off the stage like a mega-star to shake hands with the crowd. (See his site.)

Sonya Kitchell with AOD, "Trouble Child' (from Court and Spark): Teenage wonder child Kitchell has amazing confidence and range, sounding closer to the young Joni than any other performer. If she can keep it up, this is a career to watch. (See her site.)

Michelle Williams, "Help Me" (from Court and Spark): Though you might not see the link between Destiny's Child and this '70s pop hit, Williams rocked it, giving new energy to chorus: "We love our loving/but not like we love our freedom."

Bettye LaVette, "Last Chance Lost" (from Turbulent Indigo): If Joni hears this jazzy, raspy performance and doesn't love it, I'll pop out of this computer and eat your mouse. (Chomp. Chomp. Ick.) LaVette totally lost herself in the song, getting angrier with each insistent repetition of the title. (See her site.)

Cowboy Junkies, "River" (from Blue): Though I used to think the Cowboys were boring, I was just plain wrong -- now I'm a full-fledged Junkie junkie. Singer Margo Timmins' heartbreaking delivery of the line "I made my baby cry" may be even sadder than the original.

Judy Collins, "Both Sides Now" (from Clouds): If you close your eyes to block out her mane of white hair, Collins sounds -- spooky! -- exactly as she did when she made this song a hit 30 years ago. She sings "something's lost and something's gained in living every day," and it's clear that those words still hit home for her, as they sure do for me.

One last note: It seems so wrong that every yuppie in Manhattan can plunk down $4 million on a new pad, while the evening's beneficiary Music for Youth (an organization that makes up for all the cuts in school music budgets by paying for music education) struggles to get half that amount to help every school kid in New York City. If any fat cats are reading this, at least check out their site. Or else I'll get Joni to stop making nice kitty and sic her own cat on you after it recovers.