Not for me. Sticking with Snow Leopard until some less iOS-like OS X appears. If not - FreeBSD is not bad too Long time Mac OS X and Apple Mac user here. I just don't like the way Mac OS X looks/works since Lion, even it was not me, but they to pay me $30 to use it. Maybe it is an Ok OS for kids and some iPhone/iPad fanboys.
I doubt Mac OS is going away from the current scheme. But then again Windows 8 is looking like a kids OS with their Tile page. A change in desktop OS's is happening, so you better get used to it.
My Opinion: I think Mission Control is pretty nice. It's taking a little getting used to, but after a week or two my habits will change. I'm still getting used to the natural scrolling, I use it on my iPad and iPhone, so the transition will be pretty seamless. Full Screen apps are really nice. Overall, I like just about everything.
Did a clean install of Lion since my i5 2011 MBP started to act more like a turtle after the upgrade. Now, it's running like a lion (though lions are exactly known for their speed but their power )