EDIT: October 18 – This has been edited to reflect the Windows 8.1 and Windows RT 8.1 official RTM/GA release.
I've just installed the 8.1 Preview on a desktop. EDIT: 10/17/2013-this is also true for RTM. The Photos App has changed:
- No longer includes the ability to show images from Facebook, Flickr, SkyDrive
<10/18/2013deleted missing networked computers issue - for information on how to include content from supported Windows computers on a home network, see
http://answers.microsoft.com/en-us/windows/wiki/windows8_1-pictures/add-network-folders-and-display-pictures-in-the/bf3252f8-9162-4129-8387-5367e24b5609 - note that many older versions of Windows are not supported and that there is no support for Linux
based NAS devices>

- Does have some new editing features

3. Live Tile functionality has disappeared.
Edit:6/30
http://answers.microsoft.com/en-us/windows/forum/windows8_1_pr-pictures/possible-fix-for-photos-app-live-time-not-showing/e0eb3bb4-3e9c-4016-aa27-4a011ccc94a3 is
what a possible solution is to missing Live Tile issues.
Edit: 7/04
Tiles are working, but images change only 1x per day. This needs to be a shorter period.
--
Barb
Windows Entertainment and Connected Home MVP
My Blog - http://digitalmediaphile.com/
Barb's Connected World Blog Reader Windows 8 App -
http://apps.microsoft.com/windows/en-us/app/barbs-connected-world-blog/02f35769-52bf-461c-b1d5-06e54a58d298
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