" ....I've had the NuPower Ti 4800mAh battery for about two weeks now (from OWC). There is definitely an improvement over the stock Apple battery (even when it was new). I would get about 2:30 of battery life from the stock battery with only web surfing and iChat use, but with this new battery I consistently get 4 hours+, even while enjoying some more CPU intensive apps. The battery percent/time indicator doesn't work correctly for this battery, although its not a negative. The computer will show the battery is at 0%, but the computer will run for at least 10 minutes more than this before going into sleep mode. An oddity I found with the readout on the battery stats (in XBattery, which OWC recommends to see the increase in capacity over your old battery and for setup) is that although the battery should show approximately 4.800Ah, it instead shows the capacity and charge at 4.400Ah after 4 calibrations to a (now) new high of 4.630Ah. I don't see this as a problem, since I'm getting such wonderful battery life anyway.All in all, this is the best possible purchase to increase mobile usability of your Powerbook. I can't imagine the HUGE improvement that users of a 400mhz Titanium machine would see, considering the 1.5 times increase in battery life that I experienced.-Will(I asked what PB G4 model/clock speed-Mike)1GHz Titanium"