Which key/value store is the most promising/stable?

Question

I\'m looking to start using a key/value store for some side projects (mostly as a learning experience), but so many have popped up in the recent past that I\'ve got no idea

Answer 1

Just to make the list complete: there's Dreamcache, too. It's compatible with Memcached (in terms of protocol, so you can use any client library written for Memcached), it's just faster.