Good thing too, because I'm reliably informed that a surviving descendent of Conan Doyle has now obtained a European trademark on the words "Sherlock Holmes." Which should, of course, now be written Sherlock Holmes® or Sherlock HolmesTM.
How they have avoided the "generic description" thing that stopped aspirin and cellophane from remaining trademarks is beyond me, because phrases like "it didn't take a Sherlock Holmes to realise..." aren't exactly uncommon.
What this does for the vast quantity of Holmes films, pastiches, fanfic, articles etc. etc. already extant is unclear; I suspect that sooner or later there will be several VERY lucrative (for the lawyers) lawsuits, since Hollywood etc. has a LOT of money tied up in films etc. Then there are things like the old Sherlock Holmes play, which I think was also out of copyright... but now the title itself and every use of the character's name infringes trademark.
What's clear is that any future material based on this character is going to have to jump through the trademark hoops, at least in Europe. But I suspect that it will simply be dropped, with authors etc. moving on to other projects or changing names sufficiently to protect themselves.
I wonder if I could trademark the words "Greedy Bastards"