As you are aware, the return on upgrading kitchen and baths is great. So what's hot? What's going to appeal to your buyer?
Stainless steel appliances, granite countertops used to be "hot" items, but now they are expected and practically come standard.
According to the National Kitchen and Bath Association survey of more than 200 kitchen designers, cherry and maple cabinets, quartzite countertops and custom-paneled appliances are "hot" today. Even though all designers believe stainless steel is still the most popular appliance finish, 77% say that custom paneling on appliances is becoming more common. 65% of the designers see more quartzite, another durable stone material.
Interesting, Consumers have spoken in various surveys. 72% want a built-in microwave rather than a countertop model. 80% of those responding preferred a kitchen island to divide up the chores or a place to chat while fixing the meals. While planning the kitchen, see if the designer can have the exhaust go outside rather than be the filtering type.
One thing that hasn't changed is the trend toward bigger and more open kitchens that accomodate more than 1 cook. You find the "work" zone atmosphere. Kitchens are getting bigger and even more functional and it seems certain that a trend toward specialization will grow as well.