Architecture Description Languages (ADLs) sound like a great idea when you look at the "spec sheet"

ADLs represent a formal way of representing architecture
ADLs are intended to be both human and machine readable
ADLs allows simulation and analysis of architectures – completeness, consistency, ambiguity, and performance
ADLs can support automatic generation of  the system (as it is represented by the architecture)

There are quite a few ADLs out there xADL , ACME/ADML,  SSEP, Rapide,  Wright  and the list goes on and on.

I am guessing most of you didn't hear about any of those (well ACME appears in all those Willy E Coyote vs. Road Runner cartoons but that doesn't count). I think that the culprit lies in the fact that most (if not all) these come from the academic world where the focus lies on the models (in terms of semantics, completeness, rigorness etc.) and not on the practical use and applicability to day-to-day issues. Another problem lies in the fact that main-stream tools used by the industry.

By the way, UML isn't considered an ADL for several reasons for example the weak integration between the different model that inhibits automatic analysis.

The reason I am bringing the issue of ADLs up is that looking at the new architecture designers in Visual Studio 2005  (the Application Designer , the logical data center designer ,the System Designer  and the Deployment Designer) actually form a set of DSL (Domain Specific Languages) that together can be treated as an integrated ADL. Furthermore Microsoft also provides an SDK   for the"System Definition Model" that is the underlying model behind all these DSLs which lets interested parties extend and build additional designers.

While this model is not complete in several aspects ( some designers like the logical data center designer are too limited or there aren't enough views to cover all the architectural description) it is a good starting point in bringing the ADL concept into more practical and usable form.