Many Japanese textbooks of English mention the "feminine 'so'": the use of "so" for "very" is more typical of a feminine speaker. I don't think this is true in the US (I learned English living in Southern California and have now lived in the US for 10 years), but is it at all true in the UK? In other parts of the world?
Most Japanese textbooks teach American English, by the way.
[edit (responding to Mitch)] I don't have access to textbooks, but some finds online:
Yahoo! answer Japan: http://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q139835853 To a question about feminine speech, the feminine 'so' is the only example given. I think the belief is relatively widespread.
A blog post: http://ameblo.jp/yoakemae2/entry-11040928287.html "昔は feminine soと よばれ、論理的たるgentlemanは そのような 表現を 使うべきではないとさえ 言われていたようです。" (Translation: "In the past, it was called the feminine so, and it seems to have even been said that a rational gentleman should not use such an expression.") So perhaps this is only in older Japanese textbooks (like the infamous recommendation of "had better do" as a polite suggestion). Still, I'd be interested to see if there's any basis for it.