First off, AppleInsider has a few new details about the current Photos for OS X beta. Manual image zoom controls have been added to iCloud.com, as well as email sharing. Photos for OS X will launch sometime later this year, and will bring iPhoto and Aperture together, along with full iCloud integration.
Next, OS X Yosemite 10.10.2 has been released, with quite a few fixes and some updates/new features. iCloud Drive can now be browsed from within Time Machine, which could mean that you can go back and look at previous file versions stored in iCloud.