Came across the following (with no source data) on another forum. Would anyone care to comment on the reliability of the stats and/or any other related data...:

The odds for catching HIV from the following activities with a HIV infected partner, are as follows (all stats are for no condom)

blood transfusion - 90%
Mother to Child at birth - 25% (reduced to 1% with treatment)
Sharing Needles - 0.67% (no recorded cases when sterlised)
Receiving Anal - 0.5% (0.075% with condom)
Receiving Vagina - 0.1% (0.015% with condom)
Penetration Anal - 0.065% (0.01% with condom)
Penetration Vagina - 0.05% (0.0075% with condom)
Giving Blow Job - 0.01% (0.0015% with condom)
Receiving Blow Job - 0.005% (0.00075% with condom)
kissing - No recorded cases

Basically your taking 10 times the risk with BB compared to OWO, the main reason being that the virus is not in a high enough concertration within salvia to spread, and the spread occurs due to blood in the girl (or boys) mouth. Sex with a condom is more risky than OWO.

It also must be remembered that if all WGs gave BB, then it doesnt 'only' become ten times as risky, because 10 times (we're assuming contraction is only through Sex, and not drug use with that one) more people in our WG/Punter group will be infected, making it 100 times more risky.

Using a condom reduces the risk by approximately 85%. Additionally Being circumised reduces the risk for a straight man by arround 60%. (homosexual transmission is primarily through receiving, and sees no benefit from circumsion).