Yes Finally Windows 8 does provides better Multi Monitor Support even better than provided in Windows 7. Now Windows 8 provides the option of having TaskBar on every connected Monitor. The Start Menu Button is displayed on Primary Monitor and every other monitor has another quick button to Move the Start Screen to the selected Monitor. When author tested that functionality on Windows 8 with dual monitors connected to a Windows 8 computer, the start button was shifted to secondary monitor easily. So effectively you will be able to shift the start button to any monitor of your choice easily.
The Taskbars on non primary monitors are typically used to display the Windows minimized. Taskbar properties as displayed below can be used to configure what windows does the taskbars displays. As seen in the screenshot below, there are three options available to choose from. First of all you can enable or disable the taskbar on non primary monitors. Under Multiple Displays section in the screenshot below, note the checkbox which says Show Taskbar on all displays. Unchecking this checkbox will display extended multiple monitors similar to how the monitors or displays used to appear on Windows 7, Vista, etc. In case you do enable the option to display the taskbar on all displays, you can then configure what all those taskbars display ?
The options available for Windows displayed in the taskbar are to Duplicate Windows on all taskbars, Unique to each taskbar and on main taskbar, and Unique to each taskbar. Windows 8 also allows to selectively choose the option to combine the windows on taskbars in configurable 3 options.
Other things to note about Multi Monitor support of Windows 8 is that although the taskbars on other monitors can be displayed, they are not as sophisticated as the taskbar on Main Monitor. The Taskbar on secondary, ternary or other multiple monitors are limited to displaying minimized application windows only. You will be able to right click on any Window displayed on non primary taskbar and view the JumpList of the software, hover over the window icon in taskbar and preview the application window without restoring it and just like application icon on main taskbar, you will be able to close any application window on any taskbar by selecting the close option from the right click menu.
In case you would like to pin a shortcut to main taskbar, yes this will work as it used to work on Windows 7, however you will not be able to pin a shortcut specifically to any non primary taskbar. Applications launched from a shortcut on secondary monitor will not forcibly appear on secondary monitor. Application Windows will still hold the responsibility of starting up on an appropriate monitor. In case you would like to have seperate wallpaper on multiple monitors on Windows 8, you will still have to use 3rd party software application such as MurGeeMon. The MurGeeMon is a Dual Monitor Software and hence can be used only to set different wallpapers on dual monitor windows 8 computer, however developments are going on which would allow the MurMeeMon to support Multiple Monitor Windows 8 computer.