I agree, if I had a lexus w/navigation, GPS wouuldn't be an issue. But I don't think many folks share your good fortune. In regards to loading time on your BB 8800, the speed is a factor of a number of factors including the strength of the signal and the service provider (AT&T weak point). The bottom line is 3G is coming for the iPhone and the current model can't be upgraded. And like the iPod, storage capacity will most likely increase on the next version as well. Honestly, if you had the choice of an iPhone today with 3G and perhaps more storage (and not even counting on GPS), would you keep todays iPhone or wish you had the 3G version? That's the quandry you'll face in 9 - 12 months. If $600 isn't an issue, then its non-issue.
In regards to battery life and 3G, that's also a misnomer. Granted it does eat more power but not 50%. I have a 2 year old LG 4650 w/3G(Verison) with extended battery that lasts 1-2 days between charges. And that's 2 Y.O. technology.
It's certaintly a tough choice to sit on the sidelines now but it would be tougher (for me) to run the same gauntlet 9- 12 months from now with the first iPhone in tow.