O'Reilly has stepped back and has now agreed on IT@Cork's usage of the term "Web 2.0" for their conference:

Donagh Kiernan of IT@Cork (to whom the letter was addressed) graciously talked with me late in the work day on a Friday (irish time), and we've resolved the service mark issue. O'Reilly and CMP are fine with IT@Cork using "Web 2.0" in the name of their June 8 conference. And I apologized again to Donagh for the tone of our letter, and for that fact that we didn't contact IT@Cork before sending it. That's not the way we want to do business, and as a few of you (OK, more than a few) have noted, it was a mistake.

I have the feeling the media attention wasn't expected, nor appreciated by O'Reilly.
Link : O'Reilly Radar | Service Mark
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