I think there is some degree of conflation here. You can have different views/communication for session state and separate that from database state. Websocket

I think there is some degree of conflation here. You can have different views/communication for session state and separate that from database state. Websocket apps are almost invariably in the family of apps that act on some sort of session synchronization, and if you are depending on a synchronized full-view between server<->client, then yes, you will have a bad time if your working set grows without bounds. If you are more concerned with just prediction/event/streaming and have a decent invalidation/resync mechanism, then meteor becomes a natural choice for interactivity. Oh, wait, there's the first two problems in CS again — caching and naming things.