Why is Austen still around?

A friend of mine challenged me with some questions pertaining to the end of Northanger Abbey by Jane Austen a few weeks ago.  In hindsight, I realized that it's been probably 10 years since I've read that one.  This sounded like a well-timed challenge to read it again!  (I'm sure I've written this before, but surely it bears repeating: having a newborn is truly wonderful in that it affords me a crazy amount of pure, unadulterated reading time.  It's fab!!)  So I did, and then (not at all apologetically) responded to her questions with a message about 10 times as long as the one she sent me that went off on a tangent at one point about what literary "ism" Austen is truly a part of.  Trivia question--does anyone know?

And, prior to sending me these questions about a true Austen work, the same friend had also recommended that I read Austenland by Shannon Hale, a current piece of fiction wherein the protagonist ends up going on an expenses-paid 3-week trip to "Austenland" where actors are hired to portray period characters, everyone dresses in Regency clothing, and specific rules of decorum are not only expected but required.  That protagonist is venturing there after a lifetime of romantic flops to figure out her obsession with Mr. Darcy/figure out what the problem is with her love life.  But while reading both this as well as Northanger Abbey for the past couple of days, I started to wonder again about why Jane Austen's works are so enduring that we continue to get all sorts of weird (and sometimes good) adaptations and spin-offs of her original works.  Why do we still read them, too? 

There are numerous books that are written as "sequels" to Pride and Prejudice by various authors.  There are multiple movie adaptations of all of Austen's most well-loved texts.  There's a Jane Austen society (probably a festival, too).  Austen herself (undoubtedly) even makes updates on my Facebook page.  So does Charles Dickens...a post for another day!  What's all this about? 

I don't know other than she's a) a genius of her time and b) just wrote romantic (not Romantic, mind you) commentaries on genteel British life that just hadn't been done before.  Any other ideas? 

Whatever the case may be, it's good stuff.