Is 2017 the 100th anniversary of recorded Jazz?  
Yes and No.

February 24th marks the 100th anniversary of the first recording session by the Original Dixieland Jass Band by Victor. In the intervening century there has, of course, been a boatload of jazz scholarship as well as accrued mythology which invariably has added fuzz and nuance to the issue. So I suspect all of this encrustation will put a damper on any centenary celebration. And a lot boils down to the question that has perhaps never been precisely answered for the ages - what is jazz? There is also a large portion of special pleading and racialist theorizing that colors how we feel about that ancient quartet of white New Orleans musicians who came north, became a sensation at Reisenweber's in NYC and laid down their recorded notes in a pean to barnyard animals in a Victor recording studio.

So where does that leave us? 
1) Whatever you call it, the music of the ODJB was unique in terms of contemporary recording. A careful survey of the music commercially recorded prior to February 24, 1917 reveals no similar recordings. The intricate interplay among the instruments, the seemingly frantic pace and forward momentum of the music was unlike any that had been heard on commercial recordings. 
There are examples of earlier recordings that stretch the boundaries of ragtime with instrumental and vocal solos: Wilbur Sweatman's clarinet of 1916, Gene Greene's "scat vocals from 1911, James Lent (as early as 1904), and Howard Kopp of 1916 and 1917 (drums), James Reese Europe's propulsive recording of Tres Moutarde (Too Much Mustard) of 1914. But none of these compare to the combination of spontaneity and rhythmic propulsion of the the ODJB.
2) Substantial improvisation would not find its way to records until 1923 or thereabouts, and if that is sine qua non for an authentic jazz performance, these records would not qualify. They also don't represent a long term trend. Even the ODJB itself would move away from the polyphonic density of these first recordings and into more conventional rhythmic music with the addition of a saxophone and a repertoire of more popular songs of the day. Today jazz is generally considered to be a sophisticated art music based on performer improvisation and an extroverted rhythmic conception. There are other candidates for first jazz record that embody more of this current conception (again falling in the years 1922 - 1924).
3)  And what of the perhaps uncomfortable fact of a white group being the first to record jazz. Leader Nick LaRocca's crabbed racial views of his music, revisionism and speculation often based on political and racialist views, as well as honest evaluations of the roots of jazz, have made this thorny territory. But to say that the ODJB was the first to record jazz says nothing about them being the "inventors" of jazz. The concept of "invention" being as unhistorical if Jelly Roll Morton or Nick LaRocca claim to have invented it. 
Earlier scholarship trying to trace substantial jazz roots in west Africa and to distance it from American popular music of the 19th century has also been proved simplistic. The simple fact is that there is no written music and certainly no recordings that shed light on jazz's beginnings. It is only in the testimony of the early 20th century musicians active before the flurry of jazz records of the early 20s.

All this being said, let's give Nick LaRocca, Eddie Edwards, Larry Shields, Henry Ragas, and Tony Sbarbaro their due. Because of their talent, a willing recording company, public acclaim, luck, and the vagaries of race and politics, they were the first to record a unique and powerful music, not fully formed and missing what we might essentially require today in jazz performance, but heralding a sense of freedom, joy, and rhythm that makes up the great art form of jazz. They stood (perhaps unwillingly) on other shoulders, but their work stands as an opening salvo in a century of great music.