If you're anything like me, I've had Mac dock envy for ages. Then, my Dell came pre-loaded with the "Dell Dock". It didn't really have the same feature set as a Mac dock, but it was a fairly elegant way to organize your desktop.
The Dell Dock doesn't have all of the functionality offered by the taskbar (some would argue that the Mac's dock doesn't either), but I don't think it really needs to.
As for how the Taskbar stacks up against the Mac dock, I don't use a Mac enough to see enough of a difference to complain about. The biggest drawback with the Dell Dock is that it can only be installed on a Dell (duh). Not good news for my HP PC.
That being said, I finally found a free solution that I like as much as the Dell Dock...Rocketdock. With the addition the stacks docklet, it's almost identical to the Dell Dock. It may be a little bit of a pain to set up, but it meets my criteria (free and offering the same functionality as Dell Dock).The dock and info for the stacks docklet can be found here.