You go to a sprint store with a repair center(this is important). They may be able to unbrick it, if not they will replace it, but this is NOT a return. Trust me HTC has provided them with the software to try to unbrick these things.
In case you don't believe me
http://twitter.com/htc/statuses/17438994729
RT @sprint: If the 6/28 update resulted in your EVO not powering up, please go to a Sprint corporate store for help
http://bit.ly/a9UqQr
1:17 PM Jun 30th via HootSuite
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