Missed it: the New York Times has a piece on the upcoming Twilight manga with a few more details about the Twilight manga, including this piece of info:
I applaud the idea of keeping the original creators involved with later iterations of its works in general, here every bit as much as anywhere else...but this particular statement is funny because the dialogue balloons have been the subject of admonishment from comic pros like John Barber and Simon Jones (occasionally NSFW). Barber suggests that the placement and lettering are so bad that those who come to Twilight as their first comic might feel like their failure to parse Twilight properly will turn them off from comics as a whole.
“Twilight” will be split into two graphic novels. Mr. Hassler said that Ms. Meyer was involved in “every panel of every page” of the adaptation, down to the dialogue balloons.
"The balloons are giant awkward shapes...and the placement is terrible--they're awkwardly over the figures, overlapping panels randomly."
This all comes from the online preview, of course-- it's entirely possible that the dialogue bubbles will change before its release on March 16th.
(Caught it: AICN Anime.)