Facebook and Twitter Vs. Audioboo?

I've used Facebook and Twitter, and now Audioboo.  Facebook has always been my favorite, and Audioboo has not impressed me at all.  I don't see Audioboo becoming as big as either Facebook or Twitter.  I don't see what benefits Facebook and Twitter fans would see in it.  Think about cell phones these days.  It would be so much easier and more personal for people to just dial a number and talk to someone, yet they text each other back and forth 20 times to hold a conversation!  Isn't Audioboo like a talking Twitter?