I've checked the settings, deleted and re-added my Gmail account, and while it worked for less than 24 hours, I am not recieving new mail on the phone. Unable to send as well. This also seems to be the case for my Google Calendar.
I live in an area with good service and work in an area where 3G service is spotty. This doesn't seem to impact my use of the internet, or recieving the mobile version of Gmail via the web, regardless if Wi-fi is on or off.
Appreciate any help!