The 22nd annual Chicago Blues Festival testified to that, presenting four days and nights of superb music in Grant Park. And the estimated 750,000 visitors - a record turnout - showed that the blues remain a powerful draw.

Photo Credit Chicago Blues Festival

But while I thoroughly enjoyed nearly every moment, a niggling thought kept crossing my mind - who will be headlining at this festival 10 years down the road?

After all, the list of headliners looked like the roster for the nursing home's annual talent show. Taking the main stage were Honeyboy Edwards, Pinetop Perkins and Homesick James, all in their 90s. Robert Jr. Lockwood, Henry Gray and Johnnie Mae Dunson all turn 80 this year. Hubert Sumlin is 73, John Mayall is 72. Jody Williams is 70 and Koko Taylor is about to be. Buddy Guy is 68. Mavis Staples is no spring chicken.

Of more immediate concern, what could I say about these well-seasoned performers that hadn't been written a thousand times already? Everyone knows how great they are. No one needs my exclamation point. So how could I justify my presence as a reviewer?

Fortunately, I got a peek at the Future of the Blues on the festival's final night. More about that later.

Chicago is justifiably proud of its rich blues history. It's the city where Muddy Waters, Howlin' Wolf, Little Walter and so many others escaped to from Deep South drudgery, perfecting their art in the juke joints of the South and West Sides and eventually catching the ear of blues lovers worldwide. The city still has a vibrant club scene, now centered on the North Side, but with many lesser-known outposts still functioning in the old neighborhoods. And it's got this giant, free festival every June.

The festival makes a point of centennial celebrations, this year offering onstage salutes to three musicians born in 1905: the late Jimmy Walker, Big Maceo Major Merriweather and Meade Lux Lewis.

Honeyboy Edwards' 90th birthday was celebrated at three performances I caught: one afternoon and one evening set at the festival and a star-studded party at a nearby club Saturday night.

The party at Hothouse was a loving tribute from friends, family and those lucky enough to score tickets. Robert Jr., Pinetop, Sam Lay and many others sang and played 'til closing time, but Honeyboy himself stole the show during a long set. A still-nimble-fingered guitarist, he mesmerized listeners with his yearning vocals, straying off-key on occasion, but always spot-on in spirit.

Kudos to Honeyboy's longtime manager and sometime harpist Michael Frank for putting this tribute together.

John Mayall's Bluesbreakers were the opening night headliners, with multiinstrumentalist Mayall impressing with his high-pitched, sometimes keening vocals. Typically, he gave plenty of solo space to his band's latest guitar whiz, Buddy Whittington, and to guest star Mick Taylor, a Bluesbreaker alumnus from back in the 1960s. Mayall premiered work from his new CD Road Dogs and tipped his hat to Chicagoan Otis Rush ("All Your Love'') and Albert King ("Oh, Pretty Woman'').

Photo Credit Chicago Blues Festival

The queen is back on her throne. Koko Taylor looked and sounded great after overcoming serious health problems. She opened with "Let the Good Times Roll'' and roll they did, right through "I'm a Woman'' and "Wang Dang Doodle.''

Erwin Helfer is a boogie-woogie pianist, but his best moments came during several slow blues, richly embellished versions of "After Hours,'' "Trouble in Mind'' and "Sweet Substitute.'' And his unfortunately named "Pooch Piddle'' is a rhumba-rhythmed remembrance of Corrina, the dog he owned while living in New Orleans. The piece has the can't-sit-still second-line beat that defines Big Easy music.

A highlight of Helfer's set was the singing of Katharine Davis, who spiced up the already-explicit Bessie Smith lyrics on "Sugar in My Bowl.''

Billy Branch and the Sons of Blues have been staples on the Chicago scene since the late '70s. Their excellent set was the Jimmy Walker tribute and harmonica great Branch brought on a gaggle of guitar players who pianist Walker helped launch. Steve Freund, Pete Crawford and Lurrie Bell all got in their licks and jammed together on the Walker standby "Small Town Baby'' as a finale.

Buddy Guy was the Saturday night headliner and didn't disappoint the throngs who stretched out to the park's far corners. Despite a sore throat, Guy soared into falsetto range on a pair of acoustic opening numbers, then called on his band for backup on a dozen familiar tunes. On "Damn Right I've Got the Blues'' he climbed off stage and lugged his guitar and remote mic around the Petrillo bandshell, a shtick whose novelty is wearing thin.

Mavis Staples' bubbly repartee and heartfelt gospel classics proved an uplifting way to end the festival. But prior to her set came what was, for me, the answer to that question lurking about in my mind.