Another change in music criticism brought about by the internet: you might just invite a rebuttal from the musician. On the freejazz.org site (see sidebar, look for post Unity: A Lack Thereof-New Year's Eve 2006, William Parker and Friends. Check out the 117 comments so far....), Dr. Yusef Copeland wrote a negative review of a live show featuring William Parker, Roy Campbell and others. Lo and behold, Mr. Campbell took the time to wade into the fray. (My grandfatherly advice to Campbell was to quote William Blake: "The eagle never lost so much time as when he submitted to learn of the crow." Wasn't that clever of me?)
This sort of thing may have happened all the time on the NY scene, for example, but there's something interesting in the breakdown of a wall that often stood in public-- that between critic and musician. Who knows how many times musicians have decked writers outside the Village Vanguard or wherever, but the debate rarely got conducted publicly.
On the internet, for example when I post here, I'm aware that whoever it is I'm writing about might see it. The only change that brings about is for me to take responsibility for my opinions, to avoid the slimy ad hominem and the insinuated backhand, formerly in great currency among jazz writers. (a writer on Miles Davis's On the Corner when it was first released, in a two star Downbeat review: "I hate to think that anyone would be so easily pleased as to dig this record to any extent.")