Who is responsible for creating process models?
What role on a project is usually responsible for developing process models (swim lanes, activity diagrams, etc)? Is this a requirements analyst? Or is there typically a resource that is specifically a "process analyst or process modeler?"
Also, is it common practice in process modeling today to use BPMN? Or, do projects use various techniques for modeling processes?
Also, are people using formal process modeling tools for creating such models or are most of you using something simple like Visio?
Thanks!

Process Maps done by...
If you have commonly recognized roles like Project Manager, Business Analyst, Developer and Tester, it is usually going to be the Business Analyst.
Where I am today, we do have a significant number of Six Sigma practitioners who use Process Maps in their Process Improvement projects, so an IT project can often re-use existing Process Models; or, a Six Sigma person is part of the project to do new Process Models.
The use of Six Sigma drives the remaining answers. We do not use formal BPMN as I understand it, rather we have model formats as defined by our Six Sigma Black Belts... and they are in Visio.
In parallel, we do have IBM Websphere only for Application Integration, but I now have its "Business Modeler" app installed to try out; I assume it uses BPMN but don't know for sure yet...
David Wright
Member, IIBA
"I keep six honest serving-men (They taught me all I knew); Their names are What and Why and When And How and Where and Who." …Rudyard Kipling