Pluto is the farthest "planet" from the sun and its slow to make a move. As the "planet" that represents transformation, it's a reminder that all good things do come to those who wait and work it slowly and methodically. Since it's in Capricorn, the sign of structure, this is time to resort our foundations, our beliefs and understanding to be able to withstand the long haul. So, as this distant influence plays its part in the scheme of things, this new forward motion means time to take all that you now know and put it to good use, as in setting up new groundwork that you can rely on.
As for how this affects each sign, here is the list of areas in your life that you should focus on shoring up:
Aries (March 21-April 19)
Status
Taurus (April 20- May 20)
Spontaneity
Gemini (May 21- June 20)
Power
Cancer (June 21-July 22)
Equality
Leo (July 23- August 22)
Efficiency
Virgo (August 23- September 22)
Extravagance
Libra (September 23- October 22)
Foundations
Scorpio (October 23-November 21)
Communicating
Sagittarius (November 22- December 21)
Security
Capricorn (December 22-January 19)
Confidence
Aquarius (January 20-February 19)
Subconscious understanding
Pisces (February 20-March 20)
Idealism