BMW is currently using an infinitely variable variable valve timing system on the M3.
I think the M3's is the best by far in operation, being able to adjust infinitely versus being in on or off position.
VTEC is basically on or off for the valves, and variable cam timing.
Toyotas is a similar concept to hondas with the wedge activated higher lift/longer duration instead of a 3rd cam profile.

Just my $0.05 worth.