Con cancels guest 3 weeks before the con. (note: Con cancels guest, not guest blows off con)
Guest gets upset and a tad snarky. Snark doesn't negate the validity of his complaint. Sockpuppetry ensues in the comment thread (ironic, seeing how guest's wife is a well-known puppet enthusiast).
Con deletes questions about guest from their forums.
Con posts official announcement of the cancellation. Folks complain and small bits of sockpuppetry ensue again.