It is known that hurricane activity in Atlantic basin is less active than in East Pacific basin in seasons past, but for the 2005 and 2010 seasons, the Atlantic basin is busier than western Pacific basin. However,I have never heard of the eastern Pacific basin having a busier season than the western Pacific basin, is that possible?
There are many determinants of tropical storms. The most important is to have sea surface temperatures of >27 deg C. Obviously, this will increase in extent, though not necessarily in frequency, with global warming, and increased incidence of El-Nino events. Shallow sea, as in the western Pacific, warms up faster than deep sea, as in the eastern Pacific. Hence there are always likely to be more tropical storms in the west Pacific. The second determinant is for the air mass to have a 'start-up' rotation, which is a function of latitude. That is, almost no tropical storms at the equator, but many in the tropics, as air masses pick up Coriolis rotation.