The W3C has posted the minutes for the workshop a couple of weeks ago,
which have links to the presentations

http://www.w3.org/2005/06/21-xsd-user-minutes.html and
http://www.w3.org/2005/06/22-xsd-user-minutes.html
The experience reports submitted in advance are at
http://www.w3.org/2005/05/25-schema/all.zip

I was not there, but my understanding from discussions with
participants and a quick scan of the minutes is:

- XSD has numerous flaws but after 4 years we are starting to get
consistent implementations and real interoperability at the XML
document level.
- The big user problems are with schema - object mapping rather than
XSD per se.  Somebody (W3C, WS-I, domain-specific organizations?)
should address these with best practices documents.
- Many would like to see an XSD Lite that hits the 80/20 point,
unfortunately everyone seems to use a different 20% of the spec and
all features have *some* entrenched users.
- A profile that would map cleanly onto Java / .NET / C++ data types
might be feasible and useful
- Schema versioning/evolution is a very hard problem ...
-  Popular ideas on the way forward include a) a community wiki to
supplement the Primer as the source for understandable but
authoritative tutorials on XSD; b) a best pratices Note on versioning;
c) renewed focus on the test suite by W3C and test-driven development
by implementers; d) a focus on errata by the WG.

The IRC minutes end a bit abruptly just before UTC midnight, and the
link in the agenda to Summary of Action Items is broken, so there
might be a mechanical problem here?  The topic discussed at the end
was whether to go forward with XSD 1.1 or not; my sources tell me that
there was little interest in 1.1 and much interest in getting the
Schema WG to refocus on clarifications / tests / errrata.

I hope people who were there or who have read the minutes chime in
with their perceptions, clarifications, and corrections to this
summary.