There's obviously not going to be a unified opinion, but I'd point out first that, as Yoc said, no matter what anybody says should happen, the adventures are in the public domain in the country of publication, so you can use them as you'd use Hamlet or Beowulf.
That said, something I've long been tired of are modernizations that exist just to suck the fun out of everything. Personally, I wouldn't mind a twenty-first century Sparky, but I don't have an interest in seeing, say, a Sparky whose inventions invariably kill people accidentally while he does drugs and can't deal with the stress of doing good things. To me, that's not only not fun, but seems to try to remove the fun from the original stories by implying the character MUST have been like that behind the scenes.
But on the other hand, that seems to sell. Go figure...
Confusing enough...?
