I think the hype goes back further than that, with OS X 10.5/10.6 vs Windows Vista.
Windows 7 really narrowed the gap between Windows and OS X, and at the same time OS X 10.7 took many steps backwards (black & white sidebar icons, no Save As, terrible multi-screen experience).
Snow Leopard and Windows 7 marked the respective pinnacle of each OS to me, UI-wise. Windows 8.1 has some nice incremental touches... If only they'd applied them to Windows 7's basics. I haven't spent much time with newer OSXes, admittedly, and I'm basing most of my opinion here on co-workers' muffled curses.
Windows 7 really narrowed the gap between Windows and OS X, and at the same time OS X 10.7 took many steps backwards (black & white sidebar icons, no Save As, terrible multi-screen experience).