I'm an engineer with a pretty keen eye for design, but I've never understood these font wars. At a certain point, whether your serif is 3% longer, or the loop in the letter a is downwards or upwards, none of that helps or hurts readability. What companies really need to start working on is their rendering technology. The Segoe family was designed for clear type, one of the most readable and cross-screen technologies available today. Mac OSX suffers horribly from a blurriness on non-Apple displays, and as unfamiliar as I am with the tech that underlies Linux distros like Ubuntu, they haven't seem to hit any screen right yet. ClearType handles bleed, leakage, contrasts, all seamlessly. Apple has only designed for their devices, so yes, it tends to look very good on their tech. Android gets the worst of both worlds: no good algorithm, and no control of hardware.