Remember that little update thing all us Sprint Hero users were waiting for on May 7 -- Tomorrow? According to the admin at Sprint's official forums, it ain't coming. No details of any kind, just what you're seeing in the screen grab above. As infuriating as it may be, we have to remember that Sprint needs to weigh the need for an update against the end user experience, and only wants to release a product as free of bugs as possible. Ask a Motorola Droid user, they know all about it.
I have confirmed with someone at Best Buy Mobile that the screen shot of the internal memo about the upgrade was legit, so now all we can do is sit back and speculate as to what happened. My guess is Godzilla attacks. Thanks to everyone who sent this in!