Eh, like many articles the headline is a bit misleading. Vesta is most certainly
not the only original object from the formation of the solar system, it's just one of the largest (which does make somewhat special).
There have been a good number of so-called 'primitive' meteorites which contain original materials from the solar nebula --
Allende is one of the best studied of these. They put the age of the solar system at 4.567 billion years, give or take less than a million.

I'm really curious to find out what this mission will find at Ceres and how it compares to Vesta. Also what New Horizons will discover at Pluto!