How to choose suitable naming convention for Dimensional Table Column in a Data Mart?
I just completed a 4 day course with the Kimball group and they had this to say on naming conventions: 


Always use full descriptive names ie. Brand Name. and don't use abbreviations. Otherwise you may need to spend time training users.
Don't use Dim or Fact in your table names because you end up spending a lot of time deleting these from the reporting layer.
Don't use camel case or underscores, use spaces. Yeah I thought this was bizarre, but again they said you'll spend a lot of time adding in space at the reporting layer and most databases now handle spaces in column names without a problem.


If you subscribe to the Kimball methodology, then this is their approach. But like the other commenter said, it's all about comprehension. So if it makes sense for the business users, then you're on the right track.