Terminology / information model interface

I have published some initial notes on the issue of the interface
between the information model (in openEHR, this is generally archetypes,
with a bit of reference model) - see
http://www.openehr.org/wiki/display/term/Information+Model+-+Terminology+Equivalence

I am interested to know in particular what others think about the Snomed
context model, including the Temporal context, Finding context,
Procedure context, and the problem of trying to represent values in Snomed.

- thomas beale