The Space Craft posted tonight on some new features for Spaces photos (thanks, Brandon!):

High resolution photo upload,

and photo printing by HP Snapfish.

Now you can upload "hi resolution " photos by selecting "optimize photos for printing".  Note that there is no control over what that resolution is - the post on the Space Craft is exceptionally vague: "When you upload higher resolution photos, your photo albums look even better than before", and "...because high resolution photos are significantly larger in file size".

Snapfish, which HP bought in 2005, offers a number of services, including photo printing starting at 12 cents per picture, sharing, storage, editing, and the ability to create photo gifts such as mousepads, coffee cups, and the like.  The service through Spaces is available only in the US at this time, although more markets will be added in the future.