Macs actually don't upgrade processors as fast, but your point obviously remains the same. Also, since Mac makes many up-and-coming technologies standard, they do last a long time.
As for heat, it's not bad. Never really used Windows laptops on my lap, so I can't compare. But it's not nearly as bad as my PowerBook G3.
As for battery, it is true. Subject to many factors, which is why Apple gets 5. By turning down my brightness right now, I add 30 minutes of battery life. Same thing if you are using AirPort, or Bluetooth, or powering something through USB or FireWire ports. But yes, 3 hours is common.
Intel's mobile line is much much better than the PPC line, which is where the rumors are coming from. But the G5 can run cool enough to go into a notebook, they announced the chip a couple months ago. Doubt we'll see it, but IBM has one.
It's up to you, when you want to get one, get one. I don't think Apple is going to radically redesign the PB line like they did when they switched to the G4. If you get a PowerBook, you'll love it. If you can hold out using Windows for another 6 months until the switch, then do so. I'd recommend getting it as soon as you can. Why? Because the second you get the PB in your hands you'll throw your PC into a dumpster and start saving for a G5
Then you can have both, a PPC and Intel Mac.
Just be wary of when Apple releases new products. MacWorld New York in July and MacWorld San Fran in Feb are the big ones. They have the keynote, announce a OS upgrade and Mac geeks go more crazy than gamers before E3. They also usually upgrade some product lines. Same thing when they drop a product in price, like put the iMacs on sale, it means they're announcing new ones.
Re: Itunes Question
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