A fresh page from V-Jump details even more information on the upcoming Dragon Ball Kai:

The opening stuff is the standard fare we have come to expect from the earlier announcements (like “Commemorating the 20th Anniversary of the Start of Dragon Ball Z’s Broadcast!” and “The Son Goku Legend, Once More!! And its name is… DRAGON BALL KAI”). However, the interesting material appears under the header “The four points that make up the world of “Kai”!”:

• The story will be developed speedily!
  “Kai” starts from the invasion of the Saiyans. This version will be re-edited to hew more closely to Akira Toriyama’s original story, so the story’s development will progress all the faster!
• The opening and ending songs will be completely renewed!!
  The opening and ending songs will together be made anew! Furthermore, in “Kai”, the background music will be newly recorded. Let’s enjoy “Kai”, where even the music has been powered up!!
• Through digital processing, the image will be made vibrant!!
  All the grime, damage and noise remaining on the “Z” film will be removed! In HD, the image will be even clearer. We’ve carefully made the ultra-powerful “Kai” world even more impressive!
• An all-star voice cast will record the lines anew!!
  The original main cast, centered around Masako Nozawa as Son Goku, will reunite, yo. They’ll breathe life into the characters again, to support their appeal!!

So there you go. We once again are left with just as many questions as we have answers, but we are heading in the right direction. While it does not blatantly say, “Yes, we are specifically cutting down filler material”, it heavily implies something along those lines. We just have the phrasing “renewed” for the music, without any confirmation on whether or not it is Shunsuke Kikuchi’s original score as-is but re-recorded to match the higher fidelity of the newly-recorded voices, or if it is a completely new adaptation of that score. Along those same lines, the true nature of the OP/ED themes are up in the air.

We will not leave you hanging with that, though. Our buddy Wasted Wisher popped in again with a couple additional remarks:

Don’t know anything about the intro and ending song yet, or anything past episode 1.
All of the scenes that were being worked on so far are not being cropped…in fact, quite the reverse, they’re being extended. The old format of the original footage is too small to fit the standard frame sizes used for anime nowadays. So all the artwork has to be extended outwards to fit the new frame sizes; this includes both the animation itself and the background art.