Headshots that Really Rule

The Best Portraits from TIME 2010 feature work of Marco Grob (7), Peter Hapak (2), Nadav Kander(1), Peter Yang (1), Robyn Twomey (1), Platon (1), Jodi Bieber (1), Dan Winters (1), Kate Peters (1). Of these portraits only those by Peter Hapak were shot in high key.
What's in:

• low key
• use of a relatively wide angle lens
• "spot" light, on-axis or slightly off, with soft boundaries
• extra sharp not sharp enough

Strobist on the subject:  Idea: SB-III Barn Door Mod.
Looks like a nice subject for a study here....