No, sadly, these aren’t real covers for new, upcoming Doc Savage or Tintin books.
What would you give to read a Doc Savage/Shadow vs. Fu Manchu novel?
Here’s a cover for one of Tintin’s “lost” adventures where he encounters elements of the Cthulhu Mythos:
The Tintin cover is a from a small collection of four Tintin vs. Cthulhu covers available here.
[Edit dated January 5, 2011: Thanks to an alert visitor to the blog, I have discovered that there are now a total of seven Tintin covers available!]