Need for a dimensional modeling tool?

I'd like to hear opinions from members of this group about the need for a modeling tool that's more oriented towards dimensional models.
Most of us use Erwin or a similar modeling tool, which is designed for general E/R modeling (to be honest, Erwin also has a few features for dimensional models, but they are quite limited).
A modeling tool oriented toward dimensional models should be able to understand concepts like facts (with measures), dimensions (with attributes and hierarchies), degenerate dimensions etc.

One of the benefits would be the possibility to represent star schemas with hierarchies in a graphical format (see for example this image taken from http://en.wikipedia.org/wiki/Dimensional_Fact_Model):


This format could be used to document the data model and to discuss it with the client during analysis, although I think that am E/R model with a well designed star schema can be understood by non technical people.

Any comments?

ERwin and ER-Studio both have dimensional templates to capture metadata for dimensional models. The only thing ER Studio cannot do is accurately represent the relationship in a bridge table. ERwin has recently added this functionality (i.e. migrate partial PK). I am fairly content with the functionality offerred by the modeling vendors. The fact that the dimensional model does not clearly show collapsed dimension hierarchies (and several other items) is why I encourage folks to build a normalized data model of the data warehouse so that you can clearly identify these and other data issues not available in the dimensional model.

Although this is an old thread, there is still no purpose built dimensional modelling tool of note. We've built our own tool which we use for documenting the stars and for design work during customer requirement workshops. Seems to work quite well for us, and customers enjoy visualising the schema on the fly as it is developed.

I'm just tidying it up a bit, but shortly we'll be releasing a free edition into the community for others to use.