I don't think that is really a fair call to make. From the benchmarks I have seen laptop battery life is generally ranked OSX>Windows>Linux. I think the OSX advantage can be largely attributed to their total control over hardware/OS. Some benchmarks: http://www.zdnet.com/blog/gadgetreviews/windows-7-vs-snow-le... http://www.phoronix.com/scan.php?page=news_item&px=MTE2N...

Yep. IE may be more efficient than using a different browser on Windows, but it can't hold a candle to most Android and iOS devices, and there aren't many Windows laptops that can beat Apple's in tests like this.

However, this is mostly caused by poor drivers and firmware, and both Microsoft and Intel have lately been pressuring the rest of the PC ecosystem to clean up their act so that devices like ultrabooks can be viable. The resulting improvements will help other browsers just as much as IE.