I feel you. Have you used a 3GS? They are much more powerful than the 3G. My friend has a 3G and we done a few side by side comparisons, and the difference is worth very very noticeable. Like surfing the web. The 3GS will load up roughly 10 seconds faster. Scrolling is never glitchy on the 3GS like it is on the 3G. The camera has beautiful quality, especially the video recording.
Games like N.O.V.A. really show the power of the 3GS. You should check it out if you're into first person shooters. It reminds me of Halo, actually. Very similar gameplay.