I know June, July and August get the most rainfall. May & September might be included in the rainy season but I'm not sure.

If you want to go to Manila, you should go now. It gets really hot around mid-march. UA has a great fare right now to Manila. From ORD-MNL (UA ORD-HKG Philippine Airlines HKG-MNL) for like $705+ taxes. For one day in January, the price dropped to like $660 all-in.

The hotels are relatively cheap compared to similar quality ones in the US or Europe. The best ones are in Makati. The last time I checked, I believe the Shangri-La was like $150-175/night (closer to the later #). That's the best hotel there. You can get the Peninsula for $100/night but the reviews I've read said that the hotel looks like it needs to be remodeled. When I was there, I stayed in the Mandarin Oriental for a few days b/c my aunt's house ended up having fleas. I paid like $120 a night plus service fees (I forgot to add that all the hotels add on a good percentage of fees for service and taxes.). If I go back, I want to stay at the Shangri-La. The Mandarin Oriental was nice, but the Shangri-La is newer and the rooms look much better from the pics I've seen.

I can't really tell you how American's are treated as I'm sure I had a different experience that you would. I'm assuming by your question that you're white. I'm an American but of Filipino decent so I can blend in better. You'll be fine in the Makita area which has a huge shopping area close by (I believe it's called Glorietta).

I can say that getting around in the cabs is cheap, but some drivers try to scam you by not running the meter. Also, many will refuse to take you on far trips when it's busy b/c they'll make more money but just doing short trips.

If you have any other specific questions, I can do my best to answer them. I haven't been there in two years, but I am considering going in March or April if I can.