CBS/Paramount isn't stupid (unlike, say, the way Warner Bros. treated Babylon 5). I'm sure the negatives have been well-preserved. They're almost certainly in better shape than the 35mm film of the original Star Trek, since they were edited on video and thus subjected the film negatives to less wear and tear.
I wouldn't be so sure... we've seen Paramount make short-sighted decisions before, editing the 24th century shows on video tape to save money and only rendering the TMP Directors' Edition effects at 480i resolution.
It wasn't short-sighted, it was the only way to put a complex show like that on the air in 1987. Only two shows before STNG were anywhere near as complex technically on TV (Buck Rogers and BSG), and video solved a lot of editing problems.
It HAS been stated that the negatives are stored and in good shape by Paramount.