I enjoyed the ending, it made sense from a science standpoint and didn't attempt to give us an ending that didn't flow with the series. And I also liked that the series actually had an ending, so many good series get cancelled and we never get story closure.
They could have done a terrible job like the Battlestar Galacticas' ending (which was the worst I have ever seen). But then, it wasn't as good as the Blake's Seven ending or Farscape's miniseries ending.