Now that you can easily share photos here to G2G we should consider other changes to the Photo of the Week contest. (See this separate post for a summary of the new feature. It's basically what was suggested by Dorothy below.)
My thinking is that we should consider all the photos that have been shared that week as nominees.
Voting would be done by votes on the G2G post [example]. Rather than posting the nominees as answers to a G2G question on Wednesdays and voting the answers up or down, we'd just use the votes on the post where the photo was shared.
They would all be collected on the tag page: http://www.wikitree.com/g2g/tag/photos
We could continue to use photo_of_the_week instead of photos as the tag. My thinking for using photos is that it's simpler and takes the pressure off sharing-to-nominate. Some people might not feel confident nominating for Photo of the Week. They just want to share their photo. We'd be making nomination less formal. Sharing would be nominating.
Similarly, voting would be more organic. People wouldn't necessarily think of themselves as voting for Photo of the Week. They're just up-voting a G2G post where a member shared a photo.
At the end of the week, Eowyn would still create a Facebook gallery for the nominees, so there's another avenue for sharing and voting. If more than a dozen or so photos were shared that week, she could just include the top 10 or 12 vote-getters in G2G.
Members who love photos could still be selecting from the New Images gallery and sharing good photos. We'd need to do that if members aren't sharing their own photos.
If members do share their own photos, a benefit of these changes could be to make Photo of the Week more about the stories behind the photos, rather than just about the raw image. If someone shares the background and/or it spurs discussion, the post would be more likely to get up-votes and end up as the winner.