No worries about things like kidnapping in Manila but you do have to have your wits about you.

Have some common sense and dont wander off into high crime areas. The expat areas of the city (Makati, Bonifacio) are for the most part fine.

We've lived here for 2+ years and have made some great friends but it is not a city I would recommend visiting. It is pretty ugly, crowded and polluted. There are some nice restaurants and you can live like a king (or queen) as a corporate expat but it is still a 3rd world country beneath the first world facade.