Gary -
Am out of the office for a couple of days.
But, as Karen suggests, if we do not put in extra geometry types beyond
points, before we know it, implementers will be asking for an envelope or a
polygon.
FYI, thanks to the IETF folks, we have access to GML schema for ellipses
and a couple of other geometry types that are quite useful in emergency
services.
Cheers
Carl