iBook battery life

[Lowell Neudeck]

Jim Coates (jcoates at tribune.com) writes a syndicated column which deals
mostly with PCs. In a recent column he stated: ³So even those who like to
leave their laptops plugged in should force themselves to unplug at least
once every three weeks or so and run the computer until the battery
completely discharges. It is best then to let the machine totally recharge
before using it.²

He also claims that keeping the laptop plugged in all the time, shortens the
battery life because of the heat generated.

What¹s you ibookers take on that (e.g., on an 800MHz ibook with OS X)?

TIA