I know they say a MBA can only have 4GB of ram but that isn't necessarily true.
I had a Macbook (White) from Fall 2010 that claimed could only have 4GB of ram but was able to install 8GB successfully.
I had a Macbook (White) from Fall 2010 that claimed could only have 4GB of ram but was able to install 8GB successfully.
[1]: http://www.ifixit.com/Teardown/MacBook-Air-13-Inch-Mid-2011-...
The MacBook Air is a different beast in this respect because it doesn't have any RAM slots. What you buy it with is what it has, forever, unless you're much more comfortable wielding a soldering iron than most people.