playing solos and improv/shred? i can do my scales and my modes but how do i get from that to: http://www.youtube.com/watch?v=2bCpd_O5Urc

of course i can't play nearly that fast, nor is my technique anywhere in his league. but i just don't understand what makes a solo as opposed to just playing random notes in a scale. which is what i'm doing now
Try singing over a backing track instead of playing, then try playing what you sang. If you take the instrument out of the loop you'll probably naturally come up with something melodic, with phrasing, that goes somewhere. Even more so if you make up 'lyrics' too - which don't have to mean anything, or rhyme, or go anywhere, but just give you a base to structure it on.