There are quite a few ways to view what your FSMO roles are. You can use the GUI tools or even the following netdom command – netdom query fsmo
However if you are working in a trusted multi-domain environment the following command can help you view the FSMO role holders remotely.
netdom query /domain:%domainname% fsmo
This is just a huge time saver and hopefully you can add it to your tool belt of commands.