Microsoft launched a great responsive website in November. It's fully responsive from desktop to mobile and the clean, simple user interface is appealing to the eye and propels Microsoft leaps and bounds over the competition when it comes to providing users with a well-designed mobile experience. Apple needs to follow suit with a redesign and soon as their online brand is becoming more outdated by the minute! Kudos to MSFT for taking a giant leap forward with their brand and products, I look forward to what they have planned for the future.
Mini provides the best experience in terms of major car makers' mobile site designs with its crisp-looking, fast-loading mobile experience. They have really blown away the rest of the car companies when it comes to design and usability. While there is room for improvement (think car builder), they have delivered a great mobile automotive experience.
Always a brand to emulate, Zappos' mobile website is one other brands should take notice of. Their mobile site offers a great representation of their full desktop website, making it easy for a user to browse their product offerings and make purchases. Their images look very crisp on a retina display mobile device and I love their motto "Fun and a Little Weird". Zappos is a great brand doing great things in the online mobile arena.