I just swapped my 1 week old al macbook for a new one at the apple store yesterday. Wondering if anyone has experienced something like this. A few days after purchase, the light on the magsafe adapter stopped lighting up when I plugged it into the macbook. The battery meter in the menu bar still showed that the computer was running off the battery, so it didn't charge. I tried this adapter on another macbook and it worked fine. I tried the other computer's adapter in this computer and it didn't light up or charge either. Definitely not a software problem because the computer wouldn't recognize the power whether it was on or off. Tried an SMC reset and it didn't help either. The thing I find interesting is that Apple just released an SMC firmware update a few days ago that fixed magsafe issues. I tried to install that firmware after I realized there was a problem, but since the computer no longer recognized the power source, the firmware updater would not allow me to do the upgrade. I'm just wondering if the new firmware would have prevented this problem and I just missed getting it installed. The apple store genius replaced the machine without too much trouble so all is well. I scoured the web and can't find anyone complaining about the problem I had.