I love the new tabbed interface of GoldMine, I really do.
But there is just one thing that tarnishes my otherwise perfect multi-tasking experience; the size of the little red "X" you must click to close a tab.
This was actually brought up by a user at our last live training.
The solution? Use the CTRL-F4 keyboard shortcut. This will close the currently open tab in GoldMine, and indeed many other windows applications. (It's actually a spin off the good old Windows ALT-F4 shortcut, the one that closes the current Windows application)