Good to read it :)
I'm happy that this request is not cancelled

IMO, this won't be enough. Accessing/displaying images from backend 
storage is only one part of what Ansel provides. My plan is to 
implement different "remote gallery" types for different services 
(utilizing various Horde_Service_* libraries). I actually 
hacked-together a prototype of this working with Vimeo back in Horde 3 
to test the idea. This lets us be more flexible in what services we 
can support, not limiting us to cloud services with WebDAV access and 
providing a more feature rice experience for those remote APIs that 
offer more features (I'm thinking Tags, Geolocation, "likes", 
different ways of grouping photos together etc...) Any photo sharing 
site we can write a Horde_Service_* package for could be supported.

We could (and should) make a "WebDAV gallery type" one of a multitude 
of remote gallery types, but shouldn't limit remote access to WebDAV.

Since Ansel uses VFS to store the images, it would make more sense to 
add a WebDAV driver to Horde_Vfs. Then you could use owncloud or any 
other cloud storage service that provides WebDAV API.
Not sure about external specific photo/video services.

The idea is to allow Ansel to access files stored to an external resource.

Example :

Ansel displays photos stored on a remote owncloud installation.
Ansel displays photos from external media sites like Vimeo.

Ryu