"I love the community aspect of the site … "
This. 1000 times this. I _so_ often hear geeks saying "It's easy to leave Flickr, just host your photos on S3/Dropbox/your-own-web-hosting! Done!". That misses out on a _lot_ of what keeps people on Flickr. The social/community/discoverability side of it.
I suspect Flickr's successor will either:
1) be a service which provides all that "social/community/discoverability" stuff while letting users choose which of many backends actually do their photo storage (openphoto might be a first contender here),
or 2) one of the existing social networks will steamroller over the entire photo sharing space (Facebook seems to be gaining considerable momentum down this path).