The interface document was not updated for ISE 6.1i. The information contained in the 5_2i_innoveda Xilinx interface document still applies for use with ISE 6.1i.
Unzip the zip file in the "%Xilinx%\viewlog" directory.
http://www.xilinx.com/company/press/kits/ise_6/matrix.pdf shows entry tool and the devices supported by each. One important thing to note is that support for newer devices (e.g., Spartan-3) will be the responsibility on the third-party vendor. Users can still design for newer parts using another family's library, but they will not be able to use any family specific macros.