Steven Sande on his speculation that Gallery will disappear in the transition from MobileMe to iCloud:
Gallery was Apple's way of creating web-based photo albums of your photos for sharing with friends and relatives. Once again, I can't see a need for it in the post-MobileMe world. Apple has already provided an "out" to those who want to share their photos to the world -- iPhoto supports sharing pictures to both Flickr and Facebook.
Yes, there are much better ways to share your photographs with friends and family than MobileMe's Gallery. Flickr and Facebook certainly serve this purpose well. However, this is not all MobileMe's Gallery was good for.
What about photographers wanting to share photographs with clients, models, art directors, agencies, and others that are part of the project?
I use Gallery this way. After every shoot I import into Apple Aperture, rate the images and upload the selects to a private MobileMe Gallery under user/password to share with the team. The model and anybody else who worked on the project can see them and make their picks. This is not "sharing" in the social media sense, it's actually part of a workflow.
MobileMe provides a great way to do this. Aperture can seamlessly create a gallery and keep it in sync, so any changes in Aperture will be reflected in MobileMe.
Additionally, Gallery serves as a collaboration tool.
The creator can choose to allow download of the original files (ie. the RAW image), or a hi res JPEG so the designers can pull them directly from there. Quick and easy.
The creator can also allow uploads, so others can upload photographs to the gallery and they automatically sync with Aperture. Great to get together all the images after an event or a trip, for example. Or for a project where there are several photographers involved.
Plus, there's an official iPad app to view MobileMe galleries, which makes showing your work on the go easy.
It also looks pretty cool. I really hope Gallery doesn't disappear with iCloud. There's much more to it than just a Flickr or Facebook style photo sharing service.