I noticed something when I was watching anime earlier today - the sounds were much clearer than before. By that I mean that if you told me to write down (in kana) everything I heard, I would feel very confident doing so about 95-98% of the time.
At first I figured it was because I just had better sound quality - I was watching the DVDs on a laptop that's less than 2 months old. But just now I went on youtube on my usual computer (which is a few years old) and started listening to J-pop, and the effect was the same. Obviously music doesn't have the same rhythm as regular spoken language, but even so...
There's a part of me that won't believe this; I'm half-convinced that I'm imagining this or something. As I write this, I am 104 hours into the experiment. That might sound like a lot, but remember how I said that babies/toddlers take 8-11 thousand hours to pick up their first language? Even if we assume that I (at the age of 18) am "smarter" than a newborn baby, it still strikes me as being too early into the experiment for visible results. If I had had to guess how long it would've taken for something like this to happen, I would've guesstimated a thousand hours.
Either my imagination has rum amok, or I've really underestimated my own ability to pick up/get used to foreign languages.