Admittedly I'm not entirely clear on the issue, but from my understanding Jehovah was actually an earlier attempt to figure out how to pronounce the Hebrew characters that roughly translate as YHWH. Yahweh is a later, likely more accurate attempt. A similar example might be how before the 1970s, Wade-Giles was the major Chinese translation system, which translated the capital city to Peking. Later the Pinyin system was adopted for its greater accuracy, and Peking became Beijing.
The man that saved people from the Canaanites
now days people use yahuah. Or ya'uah, Jesus being yushua or y'shua
really, Yahweh is just Hebrew and Jehovah is just the English translation. from what I've read. it doesn't really matter all that much. i use Jehovah though.