In the case of Mac Portables, the original non-backlit model has a bunch of electrolytics, and they are failing nowadays. The backlit model is all or almost all tantalums. Unfortunately, the custom voltage regulator IC in the backlits is prone to failure, so most of them are dying as well. I've never seen a list of boards sorted by capacitor type. There are well-known problem children, however, like the iMac G5 power supply and PC board, the Duo Dock power supply, the Cube power supply, and the classic Mac analog board. Oddly, the oldest Apples, the Apple I and II, are still mostly OK.
My LaserWriter IIg has leaky caps too, tho it's still running, and one day I need to re-cap it. It also had an AC board failure a couple of years ago which resulted in the flashing LEDs.