Not sure if this is the same issue as everyone else is seeing, but my sync issue seems to be tied to WiFi. My sync will be working fine, but it seems if WiFi gets interrupted my sync stops until I manually sync. However, if I just turn off the WiFi, my emails start pouring in right away. This goes for all my email accounts (work from Exchange Active Sync and Gmail). I didn't notice the issue until I updated to Portico. I have an HTC 8X on Verizon.