Some risk . . . . According to the centers for disease control & prevention, "in addition to hiv, other stds can be transmitted through oral sex with an infected partner. Examples of these stds include herpes, syphilis, gonorrhea, genital warts (hpv), intestinal parasites (amebiasis), and hepatitis a." for infomation on safe sex, see: http://www.Cdc.Gov/hiv/resources/factsheets/oralsex.Htm.
Not Really. You still have the risk of sexually transmitted diseases (same as intercourse) but really should not have any additional risk beyond that. Practice safe sex regardless of what you do.