I thought Casino Royale was a good movie and a decent introduction to Daniel Craig as the character, but as a signature Bond movie? Didn't see that except for the over-reliance on the card game. I don't think the Bond torture scene was signature Bond at all--not sure where you form that opinion from. Perhaps from the books? There were some cool set pieces, no doubt, but those same set pieces could have been dropped into any generic spy thriller or Bourne movie and you would still have the same reaction--without the name James Bond entering the conversation.
Skyfall, however, has a lot of signature Bond moments and aspects that harken back to the series before Casino Royale, and in fact, before License to Kill for that matter.
Again, don't mistake me for not liking Casino Royale--it just wasn't a "Bond movie" in the true definition of the word. Just my opinion of course.