Tarzan of The Apes - Films based on the book

The book Tarzan of the Apes has been made into a number of movies (according to the Internet Movie Database there has been 89 movies with Tarzan in it's title from 1918 to 2008. Originally the first adaptions of the book to film were through silent films which appeared a few years after the book was pubslihed/the character was made. After talking pictures were introduced a popular Tarzan movie franchise was developed, anchored at first by actor Johnny Weissmüller in the title role, which lasted from the 1930s through the 1960s. After the many smaller films Disney’s came out with the animated Tarzan (1999) which marked a new beginning for the ape man, taking its inspiration equally from Burroughs and Greystoke. The newest film does however change the plot a large amount from the original book.

The Hobbit -Movie is in the process

The trilogy of Lord of the Rings had great success making lots of money as you can see from the chart below
Rottentomatoes.com provides the following statistics:

The Lord of The Rings: The Fellowship of the Ring:
Box Office: $313,837,577
VHS Rentals: $17,160,000

The Lord of the Rings: The Two Towers:
Box Office: $340,478,898
VHS Rentals: $9,460,000

The Lord of the Rings: The Return of the King:
Box Office: $376,958,965
VHS Rentals: $3,030,000

Taking those statistics for the film we can add them up and find a total:
$1,060,925,440

So after much speculation and rumors it has been confirmed that the prequel to the trilogy is being made.
The Hobbit is going to be a two part film based on the novel The Hobbit (of There and back again) by J. R. R. Tolkien. The film is currently sceduled to be released in December 2011 (Part 1) and December 2012 (Part 2) and will be directed by Guillermo del Toro, with The Lord of the Rings film trilogy director Peter Jackson serving as executive producer and co-writer.
The question is though will The Hobbit have the same success as the its books after it or just by a film for Lord of the Rings nerds to get excited about as they have nothing better to do?