go, go ,go!!!!
We came back just over a year ago and I really miss it, if I could get expat posting there we'd be back like a shot! I'm happy to answer any questions, there is also a mumsnetter who lives there, (think they might teach at one of the international schools) but I can't remember their name.
There are loads of expats there, it's a real adventure, we had so much fun and the Philippines is an amazingly beautiul country.
Just make sure your package includes international school, housing allowance and flights home. Manila has some amazing homes but is not cheap if you want to live in certain expat areas or want a pool, also as an expat you will have to accept you wil pay a higher rent than a local and you legally can't really buy there. You also might want to budget for a driver and help in the home also yaya (nanny) for the kids, it might seem an unnecessary spoilt expat luxury now but is actually more essential thasn you think.
When thinking about where to live you also need to consider traffic, it is shocking (only downside to the city) and you will spend a lot of time in the car (hence why you might want a driver...) so you need to live close to where your husband will work, where kids will go to nursery/school and where you want to shop and socalise.
Life is based around malls, with shops, supermarkets, cinemas, restaurants etc
Most expats will also live in condos by a mall or in alarge "villages" gated communities with thier own security and amenities.
The BWA British Women's Association and MADS (mothers and duaghters - dreadful name but great organsignation) expat playgroup are great help when you arrive, I met fabulous frineds throught them when I first arrived.
Few links here to start you off...
www.bwamanila.com/
www.britishschoolmanila.org/britishschool/global/index.php
www.madsmanila.com/
hope this is a help, if you tell me who your DH is going to work for and the kind of things you are into I could suggest possiblevillages /condos for you or answer any questions you have.