At home I have a pair of larger, widescreen monitors, and found that (for me) the taskbar works best vertically placed, in the "center" of the two (rightmost on the left/main monitor). I also place the couple gadgets I use (Everest system monitoring one is especially nice) on the left side of the rightmost LCD. This puts all the system information I need in a single column in the center of the overall viewing area.
I set the taskbar to show small icons/combine when full, but widened it to around an inch and a half to better show the names of the programs I pinned to it. Contrary to the way I would abuse (XP and Vista's) Quick Launch I also pin only the programs I use most often, relying on the search bar to quickly locate anything else by name.
It took me a couple weeks to get used to... But now have changed my work computer to a similar arrangement. The only issue there is that the monitor my employer provides is much smaller, so I set the taskbar to auto hide when I'm not using it to maximize usable space for this particular spreadhseet~jockey.
What I like most about the current iteration is that the same program is always in the exact same place when I go to the taskbar - and you can arrange them as you like - rather than spawning in a new location each time depending on what order you open which. For example: My eMail client is *always* the 3rd icon from the top, whether it's running or not. When I want to check mail I don't have to look for it: Muscle memory takes over. On the older OSs, I always have to stop and look for where the thing ended up before I can select it.
Suggestions for the future: Would be nice to make the search dialogue box 'Pin~able' to the taskbar so users don't have to click the Windows globe to get to it. Yes, I know there are 3rd party apps that do this. I just think it's a very simple thing to provide. Also include the ability to swap the Windows globe from one end of the Taskbar to the other.