Is there a way to split the Cmd-Tab app list onto multiple rows? Is there an app/program for OS X that will "split" the list of open apps that appears when you hit ⌘-tab into multiple rows?

This is the default behaviour for Windows 7 and it's really quite useful when you have lots of windows open, navigating with the arrow keys.
How about something like Witch? It may not be 100% what you're after, but I find it nicer than the built-in application switching.