Watch the Straight Up - Solo online guitar lesson by Jeff Scheetz from Rock Solid
Some of the more melodic players from the past include guys like Neal Schon from Journey. He had a great way of being a bit bluesy, but being very melodic at the same time.
One way we do that with this solo is by using slides to get between positions. That keeps things smooth. Then of course your note selection is the key to being melodic. Think like a singer (just don't act like one), and that will really help you hear the melodies.