I'll be honest and say this is entirely my fault - it was mentioned on the Model-Glue listserv which I don't read as often as I should - but folks should know that the latest build of Model-Glue will possibly break existing Model-Glue applications if you use the Trace() functionality.
Trace() was part of the Event API but conflicted with the built in Trace() method for ColdFusion 9. This has been renamed in Model-Glue to addTraceStatement(). (Note, the docs for Model-Glue have not been updated yet. I'll be doing that as soon as I 'hang up' here.)
This probably won't bite too many people as Trace() was really meant for debugging. This did however impact CanvasWiki. A contributor had used it a bit and I never removed them. I've updated the code base to fix this, and I've also checked in other updates as well. Nothing feature-wise, but mainly updates to make it run better with Model-Glue 2. Canvas was written for Model-Glue 1 and so it had a bunch of old 'style' things that didn't need to be there. I encourage all users to update to this newest version.