BTW, I see you want vertical splits by default, just like me. Some of us on the vim list have been working on a new option called splitvertical that would open splits vertically by default (You'd use :horizontal to override). I'd love to have you try out the patch and send bug reports (it's been my production editor for a few weeks).
https://groups.google.com/group/vim_dev/msg/679fee5026967b82