I was testing the subscription process for the newsletter plugin and noticed that welcome emails and tests emails are not sent to gmail. The results of the test run are:
Email sent with WordPress: SUCCESS
Email sent with Newsletter: SUCCESS
however, no email was received in the gmail account.
Havw checked testing it with yahoo and everything goes well.
Actually there is no much we can do. Probably Gmail is refusing email from your blog for unknown reasons. You can try to set a return path in main configuration to check if there is a delivery error response from google. You can even ask the provider to check the mail server log to see if Google is refusing connections from that server.