Since early April 2011, we have encountered email failures in Google Checkout.
The failures have to do with the alias email Google uses in Checkout (used so that the customer does not have to give out their REAL email). That makes you completely dependent on Google to deliver emails to customers.
The Google Checkout forum has reported this problem and there are lots of complaints but no indication of when (if ever) the problem will be resolved.
Contact with support is so shielded that technical support amounts to filling out a form which limits any ability to describe a problem (they basically pigeon hole you in to known issues which then are auto-replied to with typical boiler plate responses). It doesn't even look like a human is involved with support.
Anybody have a phone# for techical support at Google checkout? Anyone have more insight into this problem?