Don't know what hard or soft supposed to mean in a hypothetically ambiguous context, but the `j` here is obviously a Voiceless velar fricative (`x` in IPA). Think loch (Scott.), Χάρων (Gr.), joven (Sp.), хлопець (Ukr.)
That pronunciation had temporarily escaped me. I was trying to decide between a voiced postalveolar affricate d͡ʒ (hard) or voiced palatal approximant j (soft).
Edit: "hard" and "soft" seemed like the most logical way to describe what I thought was a dichotomy, particularly as it's also often used to distinguish between the voicings of "c" and "g".
Edit 2: Just read the whole FAQ (rather than searching for "pronunciation" or related terms), and noticed the "Where does the name come from?" entry, which mentions the Mexican origin, which is why "x" is "obviously" correct.
Regarding my usage of the "obvious": it would only be correct to say that it's obvious to me, sorry for that.
The reasoning goes like this: The word uses the Latin script in its most basic form so it's most probably some western-European language, Romance or Germanic. The phonetic structure fits Spanish the best, compared to other languages that I have any superficial knowledge on, the -ul being the most telling bit.
I say the whole thing should be pronounced 啤酒 (píjiǔ), which means beer in Chinese, just to add even more confusion into the mix :) Learning the intricacies of tonal languages is probably quicker than fully understanding Git so you still come out ahead by switching.
