I'm not sure Mr. Powell is paying attention to the continued coverage. If he is, I'd like to offer a couple of words of encouragement.
I think Mr. Powell is the only one in this story who stands on firm moral ground. He made a simple, honest mistake. All indicators point that he behaved courageously, presumably coming forward and admitting the device is missing since Apple shut it down remotely the next day. Yes, Apple management will be upset and may decide to let Mr. Powell go, but he has fulfilled his professional obligations to Apple and shown considerable courage in doing so. Future employers hiring intelligently should realize that their employers will make costly mistakes and someone who has demonstrated he openly takes responsibility and is willing to work to fix the damage they've done should be a valuable asset.
The actions of the person who found the phone are morally dubious. I don't see how you could possibly justify "playing around" with a phone you have just found while presumably waiting to return it to its owner. If this person is interested in defending their actions I'd like some proof that they did not shy away from contact with Mr. Powell (I assume he tried calling his own phone when he found out it was missing) and that they did in fact call Apple trying to get through to someone. I would also like an argument justifying their disclosure of Mr. Powell's personal details to Gizmodo when handing over the device. Something in the whole story seems a little fishy.
Gizmodo has clearly overstepped their bounds by publishing personal details about Mr. Powell. It is clear they are getting traffic and therefore benefitting from doing so at the expense of Mr. Powell. It is also clear that this is mere gossip and therefore of no journalistic value.
Apple is a large, public technology company. Applying moral or ethical principles in their case is nonsensical. What I can say for sure is that the leaked content may not have as huge of an adverse effect as perhaps anticipated. I already know a number of people who are committed to buying the new device when it comes out. I know, Steve Jobs doesn't get to announce it and blow everyone's minds at the keynote, but apart from that there may not be much harm.
Last thing. Let's have a little bit of perspective here. We're talking about a phone. And yet we have a person possibly stealing personal property, violating someone's privacy by looking at content on the phone, selling the device and the personal information to a media outlet, who then publishes both publicly, undermining Mr. Powell's career. All of this so that we get to find out about a new phone a little bit earlier. I haven't fleshed out a lot of the ethical details in my head yet, but this seems like a lot of tech geek douchebaggery.