A quick reminder in case you don't have it market on your calendars - today we're expecting the iOS 4 upgrade for the iPhone 3G and 3GS. In related news, the first pre-ordered iPhone4's have already started shipping a bit early and some of those are slated for a delivery on 23 June, which is a day earlier before the official launch date.
First, the reminder. The iOS 4 update will become available to iPhone 3G and iPhone 3GS users today. As for iPhone 2G users, don't expect the iOS 4 update through official channels. The iOS 4 update for the iPad is still a long way off - it's expected this September.
Second and third generation iPod Touch users can also expect the update today. Although iPhone 3G and iPod Touch 2nd-gen are getting iOS 4, they're only getting some of the new features - and multitasking isn't among them.