If you guys can tolerate one more post on guitar trivia

, the Gibson Derek is playing is an "SG" model. The SG was intended to be the next generation of the Les Paul guitar, with Les's name on it. However, Les did not like the SG at all. The SG was much lighter weight -- which was sorely needed because the original design Les Pauls are very HEAVY (12-15lbs) to play standing for a hour or more at a time. The SG "double cut" design also had much better access to the high frets. But the SG sound was distinctly different from the original Les Paul -- you can hear it in Derek's playing here and also in the sound of Angus Young's SG in AC/DC -- there is very little "bottom end" to the SG spound (like the bass knob, if it had one, was turned down). The difference created a distinct sound that could work very well in some circumstances, but it isn't as full as the original Les Paul guitar. You'd think the sound would get lost in all the distortion of amps, but that's not really the case -- it's pretty easy to tell an SG from a Les Paul most of the time, almost regardless of amp and pedals.
Les hated the new design so much that he asked that Gibson remove his name from it and to NOT be paid his commission on any sales, so Gibson renamed it the SG. They continued making the original Les Paul in tandem with the SG, and the original has probably proved the more popular of the two, but the SG is still favored by some.