Reg Hardware

Post: As I'm sure someone else has already pointed out...

Joe

As I'm sure someone else has already pointed out... 

In Apple power brick sparks lawsuit

...the 45 watt MacBook Air adaptor has a much more substantial connector at the laptop end, with a better cord grip. It probably hasn't had the same problems as the MacBook one.

On a personal note, while the MacBook power lead is very thin, I've had no problems with mine over two and a half years. A friend of mine has had theirs replaced twice in the same time frame, but they aren't half rough with it! (And everything else they own, for that matter.) I guess it's how you treat it - my MacBook rarely leaves the desk.