It looks like the Unrevoked team, the same one that brought you the one-click EVO root, has been playing around with some race conditions apparently present during the Incredibles' boot process, which allowed them to slowly and painfully root a couple of their phones.
The process is currently very manual and requires a lot of patience and careful timing but the Unrevoked team is not giving up, hoping to come up with a reliable method as soon as possible (they've been at it all day today).
The same hour the root instructions were released, a new root method, called unrevoked, was promised and scheduled to come out by midnight. However, Sprint's OTA update fixing the SD card issue also patched up the vulnerability that both root methods used.
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