For international orders, why the Billing and Shipping address section, the country is using the country code abbreviation, instead of country's full name? Even though customer entered the full country name during the check out?

Sometimes our order processing needs to manually print the shipping label, the country abbreviation caused confusion. Any way we can force the order to display full country name?

This will be added to 7.3.3. No timeframe yet but it is under development now.

The 7.3.3 release notes state:

Shipping
Several changes have been made to the Shipping operations in the E-Commerce 7.3.3 release that increases your customer's ability to quickly see what kind of shipping options they've selected for their purchases. Shipping methods are now more prominently displayed on the order as well as during checkout and abbreviated country codes are replaced with the full text of the country name. You also have the option to adjust your Custom Shipping Label.

When viewing an order in the Order Detail screen the full text of the country name does indeed appear. However, the <%Shipping.Country%> ns script field used on invoices still shows the abbreviated country code. We use these invoices as our shipping labels. Unfortunately the US Postal Service requires full country names, so this is a problem for all of our international orders.

Is this just an oversight in the updates made in 7.3.3 or is there some other reason this behavior was not changed?

Thank you for bringing this to our attention, I belive this was just an oversight in the update. I will bring this up with the developers, and hopefully we will have the change reflected in invoices/packing slips soon.