From my understanding server lag/latency/desync has been an issue since February, and may have something to do with the game's maximum upload-to-server rate being capped at 60kb. My friends and I have been experiencing this issue as well, and in some cases it has made the game totally unplayable, as we often run into situations where only one of us can see and interact with objects and creatures in the environment.

Hopefully we get a comment on this from the devs soon!