"Giving the guy pleasure - getting him to cum - is the entire point of a blow job!" (Jonn3)
"nice to give them pleasure, but i think i am the one who is pleasured when i am giving the blowjob. and i've never been forced to swallow..i always love to have a guy cum into my mouth when i am doing lovely things to his cock with my mouth and tongue!" (orallyours61)
To be honest (at least for me), both of you are right. The guy getting blown wants to unload his balls, but I also want him to explode in my mouth because I'm thirsty! Its a win-win scenario!
Here's the real question I want answered. Would it be weird if the guy getting sucked off didn't want to force there loads inside of you? I don't want to be forced into an act, but I'd almost be insulted if they didn't try to force the cum in you at least once. Just my thoughts on the matter.