Building a (semantic) application

Question,

Are there any examples / tutorials to build, for example, some application
using
a Semantic backend. Are there specific frameworks or patterns. Maybe I'm
ignorant
on how to achieve this because of my background with MVC applications with
an
ORM and traditional 'out of the box' frameworks.

Think it should be relevant the fact of using a semantic backend instead a
relational one in the way one develop the application. For example, I think,
there should be some kind of "Semantic MVC".

I see lots and lots of features for semantic backends and interoperability.
And
some usage scenarios, but few implementation "roadmaps" to take advantage
of all that features.

Maybe I should think about one scenario where, my application semantics,
my business domain for that application semantics, and that application
data are making worth use of all those semantics.

I'm posting my question on a couple of list, including one about rules, just
because I think patterns developed out of rules community could help me
clarify my view, and maybe have similar goals in respect to those of RDF.

Shall someone share with me this existential questions, please let me know
This file is all I could get more or less clear regarding this subject by
now:
http://cognescent.googlecode.com/files/architecturalDraft.pdf

Regards,
Sebastián.
http://www.cognescent.com