been having sync issues in the past few days (whether using beta or not).
Changes added on the web are not replicated in android, even after manually hitting "refresh". The issue happens intermittently, but is extremely annoying.
Logging out and back in seems to solve the problem (is that is any help to you in figuring this out).
By the way, reliability must be the number one feature for an app that claims to be GTD-compatible. If TD is the bucket I put everything into, I can't afford not to have my tasks, even for a few hours.