The Appendix has a Function?

Another of my cherished ideas about the world is shaken -- now they tell me that the appendix serves a purpose:

The lowly appendix, long-regarded as a useless evolutionary artifact, won newfound respect two years ago when researchers at Duke University Medical Center proposed that it actually serves a critical function. The appendix, they said, is a safe haven where good bacteria could hang out until they were needed to repopulate the gut after a nasty case of diarrhea, for example.

I wonder how I missed this news when it first came out.