Trimet has started working on OSM using the open datasets from RLIS and other agencies (http://www.civicapps.org/). I, along with a few other interns, will be attempting to help update OSM with bike routes, more accurate roads, and trails. Trimet is switching to open source trip planning software (http://maps5.trimet.org/otp/), and hopes to use OSM as the data source. But in this area, OSM's data isn't ready for routing. By the way, Trimet will be using its own transit layer in the trip planning software.
The Trimet team is pretty new to OSM, and we're gonna need contacts in this updating process as we don't want to mess up other people's work. I've been learning as much as I can as fast as I can from the wiki and mailing lists. I've already contacted a few users for information.
We will definitely want input before we do any bulk imports or automated editing using RLIS data, like bike routes, street centerlines, and trails. We haven't quite figured out how to do that anyways.
Anyhow, just wanted to keep everyone informed.