We've had the iPhone 3G just three days, but we've manged to give it a good shakedown. Today, CNET Labs finished its first round of talk time testing for both the EDGE and 3G networks. On EDGE the iPhone 3G fell about an hour short of its rated time of 10 hours, while 3G calls matched the promised time of 5 hours. Those times aren't bad, but we'll run another round just to be sure. And in any case, actual day-to-day use will be the real test of the iPhone 3G's endurance. Ideally, it should last a full day with heavy use, but in our short experience thus far both the 3G and the GPS appear to be hungry applications that drain the battery quickly. We also completed our first Internet speed tests, and we can report that the 3G service positively smokes EDGE. Busy sites loaded in less than half the time it took on the previous iPhone. We still have to run music and video playback tests, so continue to check our iPhone 3G review over the next few days.