Looking nifty, ady. A few things I noticed, if I may:
1) The other turret is back, though in what looks to be a different perspective than originally. This changes what the terrain looks like, but since you've already overtly done that, it works. It'll just take some getting used to.
2) I love the electric crackling as the cannon gears up to fire each blast. That looks great, and furthers the look you're going for in the bolts themselves.
3) Noticed the X-Wing getting blown up in front of the transport (a cool touch, but it felt like a bit of an afterthought, personally -- maybe just because at that point, you can't see any other ships but the transport). Is this a sign of more ship casualties/skirmishes to come in the final version? ;-)
4) I like what you've done with the ion blasts hitting the Star Destroyer -- the way the blasts interact with the ship looks really good (you've done a great job with the interactive lighting, too). However . . .
5) There appears to be something of a continuity error. At 00:31, when the shot changes, the crackling has pretty much subsided from the two blasts we see hit the SD in the first, frontal shot; but when it changes to the rear three-quarters view, there's some electricity going on the left side of the ship that wasn't there before the angle changed. Since there wasn't another blast coming, and the crackling down that side of the ship seemed to have subsided, the cut doesn't flow right, at least not to me. Perhaps continuing the electrical activity down that side a little longer in the first shot would fix this?
6) I like the flickering of the engine lights on the SD as it's going down, but they seem to be flickering in a pattern. It works, overall, but I found myself wondering whether they would do so in such an organized way, or if the flickering would be more random (I realize, however, that as the camera pans, the pattern allows for more engine flickering to be seen as the SD disappears offscreen).
Anyway, just some thoughts; I love what you're doing, and it's great to see a new clip! Keep up the great work, and as always, let me know if there's anything I can do to help. :-)
Take care,
Sojourn
P.S. I'm loving the 720p resolution. :-)