A friend, W, dropped by my site and asked me a question back in the office, regarding why the need for wet and dry kitchen. I told W that I'd respond on my blog, so here goes.
There is no hard and fast rule on this (not that I am aware of!) whether you should have a separate wet and dry kitchen, but in our case, the idea came from how we currently do our cooking at my in-laws, and even from where I grew up. There are always two section of the kitchen or two work-tops; one where you do the fish, cut up the chix etc, and one where you do the less nasty stuffs, e.g. sandwiches, fruits etc.
How we plan our kitchen is, the wet kitchen is where we'll normally do the 'dirty' jobs e.g. food preparation, cooking, frying where there's a fair element of fluids flying around i.e. water, oil, soups, gravies (hence maybe why it is called a wet kitchen)..... As such, the floor definitely have to be cleaned regularly so we have the wet kitchen next to the laundry area, so we can simply mop the area clean at the end of the day.
Dry kitchen meanwhile, is where we'll do the cleaner/drier stuffs e.g. baking stuffs, toast bread and it also doubles as small dining room for us, family of 5 at the bar-table which allows us to watch TV at the family room.
Maybe others can offer better explanation, but the above is how we design our house. All the oven and stoves are in the wet kitchen. Dry kitchen is where we plan to have our microwave and toaster, and my iMac and my KitchenAid (I am hinting to my Missus heheh).
So W, i hope the above answers your question.