http://www.cancerpage.com/news/article.asp?id=13212 - some really technical information about how HPV-16 (one of the two strains responsible for 70% of cervical cancers) causes oral cancers. How "genital" HPV worked for oral cancer and which strains are connected to oral cancers came up in conversation recently, so I'm posting this link. The bottom line is that HPV-16 causes a majority of cervical cancers and also causes oral cancers, although this article does not give statistics about how many cases of oral cancer are caused by 16, or how easy it is to transmit 16 orally. It's just the biological breakdown of how 16 infects the oral tissue.
http://www.doctorndtv.com/news/detailnews.asp?id=3701 - The first article I've seen that gives actual numbers regarding HPV-caused anal cancer. More study needs to be done, but these findings indicate that women are much more successful at clearing an anal HPV infection and that HPV infections last significantly shorter time periods than cervical HPV infections (which makes sense, given the much lower numbers of anal cancer compared to cervical cancer). The initial findings are such that it has been recommend that futher testing is necessary to judge the efficacy of anal HPV testing as a screen for anal cancer, and it might turn out to be inefficient, thereby removing HPV-testing of the anal area from standard screening practices.