Not really; you have the option of changing how it's presented: the new style where you can hover for windows, and the old style where each window is separate, but grouped by application. Also, an active application is more visible on the taskbar than it is on the dock; it's the difference between a visually highlighted icon versus a small light a not-insignificant distance below the icon.

And, perhaps most telling, the taskbar icons don't bounce around like a 2 year-old on sugar to announce that they need your attention.

If the OS X dock were as good as the taskbar, it'd have one item per window instead of one item per app. I'd be able to put the finder icon where I want it. I'd be able to have launcher icons (quick launch) separated from items that represent running apps or windows. I'd also be able to put it at the top of the screen if I want to.

OS X is basically rigid where Windows is flexible.