Sam draining Ruby, now that's a notion..i'm sure there are people out there who wouldn't mind getting rid of Ruby that way (me included)...Sammy seems to have a thing for bad girls though..

i could see that...he is getting stronger every time he drinks her blood.

It seems like that might work- but how lasting would the effects be and how long would it take him to drain her? It seems like the timing would have to be just right for it to work. I think Sam would do it if push came to shove. Killing Lilith is way more important to him than Ruby is. I also think that that much blood would totally warp him- he wouldn't be Sammy anymore.

...which would still involve him drinking her blood, but I don't think he'd want to kill her...yet! In "On the Head of a Pin", I'm pretty sure he was saying the effects don't last; "I'm not as strong as I was", or "I'm not as strong anymore", something like that. I think Ruby's blood gives him a demonic turbo-boost that advances his powers more quickly than what he's ready for, and maybe that's why it doesn't last. If he took too much, I honestly think he'd OD. He just has to wait, or find another way to take out Lilith.

>=[ GRRRR. I want Ruby dead! =P

It might end up that Sam has full Demon Blood at the end of season 4.That way he won't be Human anymore.
I hope not.