Here's a swing. Hope it's not a miss.

So yeah, it took awhile to figure out what this reading meant:

http://www.stanford.edu/dept/HPS/Baudrillard/Baudrillard_Simulacra.html

So I'm trying to think of it in terms of digital media.  I'm just amazed I actually encountered a word I had to look up.  So, anyway, here's my attempt at an interpretation.

I can see that the author is seeing a threat with digital media becoming a new form of simulacrum, the threat being that reality itself is starting to become blurred.  Digital media, after all, is different from maps, books, or even music, in that whenever a simulation of anything real is digitally made it can be copied over and over again, remade, remastered, redone.  You can create a simulation of a simulation of a simulation.  When something is simulated so many times from the real thing, over time I can imagine that the reality itself becomes very hard to perceive--almost getting lost in all the translation.  I think Wikipedia is a good example of this--Wikipedia has become a popular source of information, even though the reality that information portrays is changing every day with different people entering different perspectives.  In the end, which part of that Wikipedia article is actually true, and which part just came from a bunch of vague sources of the information in an overly-generalized form (generalized enough that the parts of the truth are eventually lost)? I could even see Google Earth going down this path.  How many road maps on the internet do you see that are Google Earth? And some areas of Google Earth are dated, while others aren't--leading to discrepancies in the reality of the Earth's layout (my folks' house does not appear on Google Earth...nor does the field beside us.  It was woods--clearly shot before that area was developed).

For this reason, while digital media is certainly a blessing (with more and more information becoming available worldwide), it can equally become a curse if it's relied upon too much.  We must not forget the real world exists, and that some truths we can only find if we search reality for it, and not the Web.

Of course, had Magellan had Google Earth at his disposal (or even Wikipedia), this might not have happened

http://www.youtube.com/watch?v=pM-igYjn6E4