I more often find myself in situations where I am reading a review (or even forum post) and seeing something that makes me think "Wow. That was kind of insensitive to a certain group of people," rather than "I personally feel offended and hurt by that." Maybe it's because I don't identify with many labels? For example, when I see someone using a derogatory term for homosexuals or transgendered individuals, I find it offensive on those individuals' behalves, not my own.
The things I find offensive, personally:
--"Made in China" listed as a con. I admit that I am SUPER biased in this, since it's a country (sort of) near and dear to my heart. I don't think that people realize that if it's shoddy worksmanship, it's not technically China's fault, it's the company's fault for being cheap. There are products made in China that don't contain lead or buttons that fall off... they're just less cheap to produce than the ones that do. Anyway, it's just indicative of a sweeping generalization--"All things made in China are crap"--that I find offensive. Not just because I disagree with it, but because it feels like an ignorant, arrogant, statement.
--Insensitivity towards less-curvy women. This doesn't make me mad, it just makes me sad. Even though hormonal birth control may have supplied me with slight curves that I'm not genetically entitled to, I still feel like a skinny, flat-chested woman inside. When I review something that's meant to be worn, whether it be lingerie or a harness, I try to include all body types into my review. I steer clear away from terms that favor one body type over the other. So when I see a review (or article or post) that suggests that curvier women are more desirable because only their bodies are realistically proportioned, I feel like I'm being called an anorexic, underfed, stick person.
Soooo not much, really. More often, what I find offensive is actual behavior on the site. Someone will give criticism on a review, and the reviewer will be so incensed at this criticism that the reviewer will proceed to yell at the voter, privately or publicly, until the voter either apologizes or ignores the complaints. This particularly annoys me when the reviewers themselves take pride in being critical voters. When questioned about their critical votes, they will claim that they're helping the reviewer grow. That's very good, but when these critical reviewers receives critical votes? They hound the voters down. Double standard much?
Of course, there are critical voters out there who can give AND receive critical votes and comments courteously. For these members of the community, I am thankful.
Finally, bullying of newer reviewers. This never happened to me. When I was new, the more experienced members of the site were great to me. I felt guided; I felt mentored. Now, however, I'm seeing a rise in disrespectful behavior from the veterans to the newbies. Not every newbie is a bad reviewer--we should be helping them out, not shouting them down!