I am very excited to get my Iphone 3G on Friday...(maybe), but I am very concerned now about the GPS. I used to have a blackberry with built in GPS and was able to get turn by turn directions by using telenav. According to the review the GPS isn't good enough for this..!!??! So, What about the TomTom software that is supposed to be heading our way for it? If it has GPS and can track you live why can't GPS turn by turn be used? I am confused.