In addition to a refreshed 12-inch MacBook, Apple has also announced that it will be bumping all 13-inch MacBook Air configurations to include 8GB of RAM. Previously Apple charged $100 to upgrade to 8GB from the base 4GB option. This change does not affect the base 11-inch model, as that will still have 4GB of RAM to start.

MacBook Air

From Apple's refreshed 12-inch MacBook announcement:

Apple also today made 8GB of memory standard across all configurations of the 13-inch MacBook Air.

The $100 savings on upgrading the RAM makes the MacBook Air an even more enticing purchase for someone looking for ultra-portable without sacrificing all the speed and power.

See at Apple