The last time Apple released a new version of OS X, we came away feeling a little... underwhelmed. Don't get us wrong: We'll never say no to a free software upgrade. But despite a handful of new apps and features, last year's Mavericks release still felt like the same old OS X. You can't say that about Yosemite, though. The company's next-gen operating system ushers in the Mac's biggest makeover in years, with a flat, streamlined look inspired by iOS 7. Yosemite works more like iOS too, particularly the part where you can route phone calls to your desktop. You'll also enjoy improved Spotlight search, with results that include news, local restaurant listings, Wikipedia pages, movie times and quick unit conversions. Safari works much the same way, and includes some enhanced privacy settings, too. Right now, Yosemite isn't quite finished -- it won't arrive until sometime this fall -- but you can sign up for the public beta, which will open tomorrow for the first million people who enlist. In the meantime, I've been using an early build for a week now. Here's a quick preview for those of you who can't wait till tomorrow.