Gong Hay Fat Choi (which means: Congratulations, Get Rich!)
Here is my prognostication:
Rats are the smartest of the twelve animals. They like to tear and chew things into tiny pieces and put them in piles. If you haven't throw it away already, you might as well wait until the ox year. Rats are not actually good organizers, but they save everything and know how to find it again by sheer mental prowess.
So it's a great year for beginning a course of study, for taking exams, and in depth research, starting a collection, or adding a room onto your house (for storage).
After the pig, and the snake, the rat is the most sexy year. This being an Earth Rat year it is good for partnerships, nesting, and babies. Rats like company so it's a good year for people in businesses that thrive on social activity.
If you are a tiger, be particularly careful of over-eating, rats make easy meals but too much of a good thing will lead to lethargy by the summer months.
If you are a dragon it could be a tough year, get people to help you with the small stuff, the normally grand plans of the dragon are likely to get bogged down in minutiae. Ditto for the horse.
It's a good year for monkeys, rabbits and oxen.
The nose and whiskers of the rat are extremely sensitive, so the first part of the year is great for planning and seeking out new solutions to old problems. Look for new sources of income and new markets.
The rat year is great for experiments. Heightened sensitivity makes intuition more reliable. And even if you botch things up rats are always good at getting out of a corner or squeezing through a tight spot.
Start preparing now for next Winter. It's likely to be a long, tough one where things (like the rat's tail) get strung out. If you get a chance to finish projects in October or November, take it and then go into retreat, otherwise you may find yourself working on the never ending project--lingering into the ox year.
The key to a good rat year is knowing that rats are very flexible about what they eat, as long as they don't bite off more than they can chew.