hey! I'll be in Extremadura too! I didn't really know much about it, but have been doing some research too... (I still hope someone that's actually been there answers this, but just thought it'd be cool to get in touch w/ someone else that may be there, and start a dialogue about the region!)
I've been playing around in Google Maps (if you type in something like "bar" and a city name, there are at least a handful in Plasencia, Badajoz, Caceres, Merida, and Zafra, and random places scattered elsewhere)... But we'll supposedly have Fridays off (i.e. 3 day weekends), so if the nightlife leaves something to be desired, you could probably head to Madrid every weekend if you wanted to... or Salamanca, Sevilla, or even Lisbon depending on which end of Extremadura you end up placed in. Personally though, as a small town girl myself, I bet the house parties are where it's at...

Extremadura seems to have a lot of places of historical, cultural and ecological interest. Roman ruins, wildlife refuges, the Wolf Vostell Museum, a wine region (check out
http://www.vinosdeextremadura.es/ ), cathedrals and castles and art museums (take a peek at
http://www.fexm.es/temas/cultura/museos.htm ), etc. There's lots of info. online, some of it is a bit hard to find - if you're interested in any of those things, I can post more links. Much of that is not traditional fun for young people, I guess... but I'm VERY excited about Extremadura! (I made it into the program by the skin of my teeth, so I'm just thankful for what I got!!!)
This NY Times article is a good overview (it's from 1998, but it probably hasn't changed much, LOL):
http://www.nytimes.com/1998/05/10/travel/land-of-the-conquerors.htmlA friend of mine has gotten in touch with someone that was placed in Badajoz for the '08-'09 school year, and she seems to love it! But it seems like the experience is different for everyone, and it's partly what we make it...
If none of that interests you (no judgment, we all have different interests), I would also say that declining the grant is an option. Or maybe you could talk to someone about switching? But I hope that you'll come to Extremadura w/ me, I'd like to have friends there!!! haha.

Saludos,
Becca