Question: What time of year can I dive the Philippines?
Answer: In terms of water temperature and visibility, any time of year is just great - the water temperature is around 28C. What you do need to be aware of is typhoon season which typically extends from August to December. The typhoon belt starts at 10 degree latitude which is more or less north of Cebu City. Thus choosing dive sites below Cebu City especially from August to December, you should be reasonably sure of avoiding lost diving time through typhoons.
Question: What type of wetsuit is appropriate.
Answer: A 3mm wetsuit should keep you warm enough. Some "thick skinned" divers are even comfortable with a 1mm skin. Shorties are fine but long westuits can be useful when there are jelly fish around. We often come across really small jellyfish which are hard to spot but still give a sting.
Question: What can I expect to see?
Answer: In general at good dive sites, you can expect to see a diveristy of hard and soft coral, a lot of macro critters, and a good mix of reef fish. Genrally fish polpulations and fish sizes are on the low size due to over fishing. Check out the dive books and dive forums to find out the special attarctions at each site. For example the major special attraction at Moalboal, Cebu are the "clouds" of sardines to be found at Pescador Island. These shoals of fish attract many predators such as jacks, barracuda, tuna and thresher sharks. This really is a site not to be missed.