While most planets orbit the sun in a flat disk called the ecliptic, this new Kuiper Belt Object is at quite an angle, nearly 45 degrees out line! It is also quite far away, nearly 100 times the Earth-sun distance, and twice as far from the sun as Pluto.
This discovery is sure to re-open the whole "is Pluto a planet?" debate. But, at the very least, Clyde Tombaugh, the discoverer of Pluto, can be said to have discovered the first object in the Kuiper Belt 21 years before Gerard Kuiper hypothesized its existance!
More information on 2003 UB313 can be found here.