I just read the follow-up to a thread (Why we need explicit temporal labelling) on the formal modeling of time and time related semantics to RDF, specifically. I wanted to put my $0.02 in since, I spend a good deal of my time at work buried nose-deep in large volumes of bioinformatic cardiovascular data, most of which is largely temporal. I guess, to put it succintly, I just don't see the value in merging temporal semantics (not a very light weight model) into the fabric of your representation model.
We found (for our purposes) that by including our own specific temporal semantic vocabulary, we could ensure that we can answer questions such as:
How many patients had complained about chest pains witin 30 days of a specific surgical operation.
While at the same time avoiding the rigidness of temporal reasoning that formal models impose. Such formalisms (especially in distributed systems) are unecessary when you consider that most often, data as it is fetched (at any point in time) is 'complete' regardless of how it has varied over time.
Consider the RDF schema for OWL, whose identifier (the identifier of the URL from where it's content can be loaded) includes some temporal semantics (when it was published, and the suggestion that there are prior versions). Though the content might have changed over time, the entire document as it was at any point was 'consistent' in what it conveys. No additional temporal semantics is needed to capture the relations between versions or to maintain some 'sanity' (if you will) over the fact that the data changed over time.
And if such formalism is needed, it's rather easy to piggy back off existing ontologies ("Time Ontology in OWL" for instance.)
Furthermore, If you think about it, named contexts (graphs, scopes, etc..) already provide a more adequate solution to the issue of inconsistency of data (over time) from the same source. For instance, you can take advantage of syntactic RDF/XML and N3 sugar such as:
<> a owl:Ontology; dc:date "2002-07-13";
or it's RDF/XML equivalent:
<owl:Ontology rdf:about=""> <dc:date>2002-07-13</dc:date> </owl:Ontology>
In order to capture enough provenance data to accomodate change.
Ironically, the ability to make provenance statements (one of which includes the date associated with this 'representation') about a named graph (identified by the URL from which it was loaded) is beyond the semantics of the RDF model. However, through it's use you can be specific about the source of triples and (in addition), you can include the specifics of version either within the identifier of the source of through provenance statements made about it.
I think the problem is more a modeling issue (and having the foresight to determine how you accomodate the change of data over time) than a shorcoming of the framework.