I get that Java has liabilities itself and that XP has them itself, but what I mean is is it that the XP + Java 8 combination is somehow particularly bad? Doesn't seem to me to be the case from what they say in that FAQ, seems like they are just saying Microsoft doesn't support XP any more so XP has liabilities, so nothing to do with java, nothing to do with having java 8 on XP, just XP's own liabilities.
Regarding what websites I visit that require java, I can't remember, but I get the "need java enabled" with some frequency. I think its not any site I visit regularly, but one off sites, but it happens fairly frequently.