I love adventure. My biggest irk with the new Star Trek is that they've taken the action/adventure that ToS and NextGen were so great at and basically removed any adventure. I think the concept of adventure is better suited for different mediums. While stories like A Wrinkle in Time or Alice's Adventures in Wonderland can captivate me with their adventure, they just don't have the same impact as playing Zelda or Super Metroid.
I agree with previous posters. The definition of adventure is such a broad one, and today it is even broader. If it's good, people will want to read it, period, in my opinion.
I have not picked up any of the Clive Cusslers Novels, but i do read the Andy McDermott adventure novels, they are really good.. I highly recomend them.. I am eager awaiting the release for his next one, i folow him on twitter.. The genre is far from dead, its like the imagination, the possibilites are endles.. there are authors now that is leading the way in this genre....Our planet has a very rich history, and pre history, and ancient history.. History is full of secret societies, and lost civilisations. so much there to inspire.. I am working on a concept at the moment of a Atlantean society still remaining today in current times. in hidden out post and cities. Its set up in scotland mainly, which will include the mystery of Loch Ness, as a side story.. but will include other locations. with current day characters.. It means a fair bit of research for locations, etc.... and an excuse for a holiday in scotland later this year..