http://chemistry.about.com/od/foodch...t-Of-Water.htm
http://chemistry.about.com/od/soluti...ntele.-NxZ.htm
http://www.knowswhy.com/why-does-sal...r-boil-faster/

I'm sure I could link more stuff, but adding salt may actually make it boil slower

Barely though. It has very very little effect on it unless you add a crap ton of salt.

Basically after reading a few pages on this it seems that it may make the water boil more slowly but it will be of a higher temperature when it does boil, meaning the food will cook faster. But again, you usually need a good deal of salt.

i put my pasta in with the water before it boils anyway so it makes very little difference to me