This may be related, but my issue is different.
I played for a few hours earlier this afternoon and got no credit toward any achievements, at all. No toasts, no progress bar increases - nothing.
Gold is at 0/whatever. Elites killed is at 0/whatever. Jar of Souls event completed - no achievement even triggered. The actual kill stats on my profile seem accurate, but absolutely nothing has any progress in my achievements data.
Possibly related useful info: I did play in the open beta weekend a few weeks back and got most of the beta achievements there. Also I am in the UK on the EU servers. We don't get these fancy Bug forums over there.