Now this is eternal life, that they should know you, the only true God, and the one whom you sent, Jesus Christ.
Hell exists pretty much specifically for people who don't know the only true God and the One Whom He sent. By definition, the damned don't have eternal life. And, as Rob pointed out, there isn't some dualistic or indifferent Eternity, part of which is God and heaven and goodness and life and part of which is Satan and hell and evil and death.
As I understand it, what this means is that human life in the "new earth" will be both everlasting -- in the sense of unending -- and eternal, insofar as it will be a participation in the Divine Life of the Trinity.
The damned, on the other hand, will not participate in the Divine Life, and therefore will not experience eternity, though their existence will be everlasting.