I found a third-party system tray utility that allows hot-swaps to happen; it's called HotSwap! & works like a charm. Click on the icon, select the drive you want to remove, and it does the following to allow the drive to be removed:
* Compatible user interface with the "Safely Remove Hardware" icon on Windows XP.
* Confirms all volumes assigned to the drive are not in use before removing it.
* Spin-down the drive to remove the drive safely.
* Not only fixed disk drives but also other type of drives can be removed.
* Runs without user interface by given command line switch and also the message popup can be suppressed.
http://mysite.verizon.net/kaakoon/hotswap/index_enu.htm