...and mind you, I use my iPhone for practically everything EXCEPT video. It's just not a good idea except for bragging rights. Though, when they come out with an iPhone that has a 35mm sensor and XLR jacks, I'll change my tune.
I would sooner buy an XLR adapter that had an ipod/iphone dock on it, so I could get better sound into the iPhone/ipod, and the adapter could already have a tripod screw port on it to fit onto a tripod or a shooter's handle.
Not according to these guys (linked below). Not that I endorse the Smoothee thingy, or using the iPhone to shoot any serious videos...but there are many excellent examples out there that make you thing about, "using what you have now".