GRUB UI suggestion

[Dave Yost]

When you change the startup system selection in GRUB, your selection 
should become the new default.  To me this is obvious.

A nice addition would be a checkbox that would allow booting the 
selected system this time only (i.e. not setting the default).

You could reach this checkbox simply by hitting down arrow and modify 
the checkbox by hitting space or return.

Thanks

Dave