Beware of some taxis. It's bad enough for the locals but it might be traumatic for unwary foreigners.
The last time I was home (I live in Australia now but am a Pinoy always ), I learned that the problem with 'good' (honest drivers) and 'bad' (the ones who'll take you the long winding way or set up their passengers for hold-ups by accomplices) taxis got worst...
Day trips to Pagsanjan waterfalls and Tagatay volcano are nice but be prepared for some serious hawking of souvenirs, drinks and like lonely planet says 'the high tips agressive boat operators demand'. The best thing is to book a package from your hotel so you don't have to negotiate with them - otherwise you will pay more for the boat across the volcano lake than for a whole day trip package from Manila.