.cc IMO is a nice cctld, don't have any myself but have never minded seeing them around, nor would be surprised to see an upsurge in them. Cheap to renew. No trustees req'd for ownership. There was a member here awhile back, he was selling example/cc, which is a rarity, for a few hundred. Most extensions have "www" or "example" left-of-the-dot restricted.
Haven't come across any .cc's in real world usage. Don't know what's holding it back, but it's a fine extension as far as I'm concerned, nothing against it. Wonder if it could just come down to semantics, maybe "cc" just doesn't jive with folks?