Re: Allowed in Islam ?
Here are few links
http://www.answering-christianity.com/oral_sex.htm
http://www.islamonline.com/cgi-bin/news_service/fatwah_story.asp?service_id=318
http://www.islam-usa.com/s8.html
http://www.islamonline.net/servlet/Satellite?cid=1120469512363&pagename=IslamOnline-English-Cyber_Counselor/CyberCounselingE/CyberCounselingE
http://www.themodernreligion.com/misc/sex/sex-oral.html
here are the ones who disagree but they are also extrapolating the meaning of Ayat 2:223
http://www.understanding-islam.com/related/text.asp?
http://www.central-mosque.com/fiqh/OralSexInIslam.htmtype=discussion&did=185
Islamic invitation Centre
Both the lists keep on going but allowed are in majority, however even disallowed have given it Makrooh but not haram because their is no such clear cut injunction. so if you wanna go ahead, your choice, Islam does not stop you.
The more interesting the debate is about anal sex, i was surprised to know about this debate while searching for the oral sex question as i never even thought that it is okay, however there is a group of Ulema who considered it as allowed but with permission of wife. Most notable of them is the Grand Ayatollah Ali Sistani. another Alim had rejected on natural makeup however has stated that all the four hadith about this type of sex with wife are not authentic enough to apply hurmat.
However i by no means am advocating in its favor as i expect a severe backlash, i was just informing your folks about the presence of debate.