Reddit’s prospectus for its initial public offering finally dropped on Thursday, complete with the customary list of “risk factors” that the company thinks could give it headaches in the years ahead as a public company. At 40,000 words, it’s longer than Facebook’s and Twitter’s risk factor statements combined at the time of their listings. As with IPOs past, many of them are boilerplate. An earthquake would be bad for Reddit’s business, for instance, particularly if it happens to occur within sh...