DSL

At a DSL workshop I organised in June (http://wiki.portal.chalmers.se/cse/pmwiki.php/GSDP/DSL4EE) Fritz Henglein presented his group's work on DSLs for Enterprise Resource Planning: http://www.cse.chalmers.se/~patrikj/DSL4EE2011/DSL4EE_Henglein.pdf
One of the resulting publications is "POETS: Process-Oriented Event-driven Transaction Systems"
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.163.2167

So, if this counts as a partial answer to your question, then Yes, it is worth it, but No, UML is not the path I would recommend.

Also Jeremy Gibbons' talk at the same workshop is about a successful example of implementing an "information system" - in that case in the medical sector (CancerGrid project): http://www.cse.chalmers.se/~patrikj/DSL4EE2011/DSL4EE_Gibbons_dsl4ir.pdf

/Patrik