I'm addicted to multiple workspaces, currently I have 20 workspaces in 3 rows.
Sadly, XFWM only supports keyboard shortcuts for the first 12 workspaces. I've opened a bug in Red Hat bugzilla against Fedora 16 where Kevin Fenzi pointed out that this is hardcoded in XFWM.
I'd love to see some dynamic support for desktop switching shortcuts. Either providing option to add shortcut up to the number of currently configured desktop. Or via some macros (switch to desktop $X -> ALT+$X, switch to desktop 1$Y -> CTRL+ALT+$Y). Or any other solution that might allow me access desktops > 12 by keyboard.
The Fedora bug in question is this: