Here's my 2c on this whole situation....(Let me just say I am a NON-SHIPPER)
The way I see it, Firstly, Sam becomeing involved with either Jack or Danny would totally suck. Not only would it ruin the show, but it would get boreing. Let her go out with someone who isn't SG1. Davis seems to be everyone's preference for that (he'd be good). The group dynamic they have as close friends is fantastic and a relationship would just mess it up and ruin the characters.
In solving this argument there is one point that I think is very valid. Fan Fiction. Although we don't want to see S/J getting it together on screen, alot of writers pair them up in Fan Fiction. These can be sometimes be enjoyable to read if you think they should be together. So instead of seeing it on screen you can get it from FF. That way, the non-shippers don't have to see S/J on screen, but shippers can read about it which can be just as good as watching it.
As for the shippers who say they won't watch the show anymore if J/S don't get together, I highly doubt that. Why would you not watch one of the most fantastic SciFi shows of all time just because the two main characters are not 'gettin jiggy with it'? The show has so much more to offer than tbat. If you stop watching it for that reason, then you have missed out on something wonderful.