FWIW, the RESTful hashtable (pita) is pretty handy for building stateful flash apps - that is, thicker clients that want to be able to save/load, and just stash their per-user state someplace. Slap on some standard metadata, authentication policy, and data-pocket mgmt and you have yourself a really useful mini-app.
No, this would not be used for lots and lots of frequent hashtable lookups within a program.
While we are on the topic, I have also written a post. on why this design is important for people concerned with freeculture.