I vacationed in Manila last summer, living with my cousins.
Watch out for kidnappers. Their security guards carry assault rifles. I assume that's an indication of how unsafe that place is.
Other than that, great country. Cheap labour. When I went golfing at a driving range, I had this girl sitting in front of me, placing the golf balls in front of my by hand. I didn't hit her with my club, thankfully...
You'll have to get used to people opening doors for you and calling you sir. You'll enjoy it as long as you're not a human rights activist.
I personally was quite disturbed.