Mee neither. I was a fool for picking up an iPhone (first time owner) recently without doing any prior research so I didn't know about the pending 3GS. I was obviously mad at myself when they announced the 3GS just a few months after I got the 3G. But luckily for me, it's really only faster since the most significant features are part of the OS 3.0 upgrade. I'd be real pissed if they made push notification and tethering 3GS only.
Given the modest upgrade this time, I imagine that Apple is probably preparing a killer 4th gen iPhone in next year or so. Cool thing is, iPhone is no longer just a smartphone, it's a platform. And a platform with a large and growing user base that you can always count on constant new releases of cool apps from developers.