Voe -
Sorry for the late reply. I've been enjoying my 680 too much.
As for why I wanted a Treo, bottom line is I love my Palm OS PDAs, but need a keyboard. Never could get the hang of Graffiti, and don't want to drag around a Bluetooth keyboard.
I bought a ThumBoard for my Visor Deluxe, and bought the Tungsten C largely because of it's keyboard. Since no one makes a POS PDA w/ keyboard, my option was a Treo. I'm currently w/ T-Mobile, and don't want to switch carriers. So the 700P isn't an option. I almost bought a 650 a number of months ago, right about the time the rumors started flying about the 680. Decided to wait it out. I'm really glad I did.
I also love having my address book in my phone, without having to enter info in twice. THAT was becoming a real pain.
Hope that helps. Please feel free to ask any other questions.