i dowloaded the new itunes today. july 11. the day the new iphone 3g comes out.
and i hurd today is the day the 2.0 update comes out. when i click the check for updates, it brings up a bar on the screen, looks like its going to dowload the new update. but then a tab popes up blinking so i clicked it, and it says,

"the iphone update server could not be contacted.

make sure your network setting are correct and your network connection is active, or try again later"

obviously im connected to the internet, so i tried again later and same thing..

what do i do???

Wait. Apple has bitten more than it can chew today - it has launched the iPhone 3G, MobileMe and iPhone and iPod Touch 2.0, and of course their servers have been brought to a standstill.

There are other ways of getting the updates, which you can find links to at http://www.macrumors.com