i have a BC rich mockingbird electric and a fender acoustic/electric.
learning a few songs here and there is actually not difficult... you can learn to play smoke on the water, iron man and a few easy songs (normally excluding the solos) quite easily, but to actually understand scales and be able to write your own music takes much more time. if you keep it up you will develop an ear for the guitar... i know personally i sometimes listen to music and i realize that i actually didn't even hear what the singer sounded like i was listening to the guitar only...
it's a lot in how much you play... do you have someone who will show you some pointers? in my opinion it is more difficult to play the acoustic than the electric. it seems the action (action on a guitar is the amount of space between the strings and the neck meaning you have to push the strings further down) is normally higher on acoustics, but maybe thats just a coincidence for me...
the only surefire thing to do is practice, practice, practice...
also this may be a shortcut many people are interested in... the new rockband 3 is going to offer an actual six string guitar, so you may get to learn to really play the guitar... not a piece of plastic. i don't know how it's going to look/feel yet, but it would be cool if it was an exact guitar that you could actually learn