Roberts was nominated when O'Connor announced her retirement and vacancy on the court
Then Roberts was then nominated to fill the vacancy of Chief Justice when Rehnquist passed away.
Ailto was nominated when O'Conner vacancy became open again when Roberts didn't fill it
Exactly! We agree.
Actually, Roberts was withdrawn for the O'Conner seat, and then nominated for the Rehnquist seat.
Then Bush refused to nominate a replacement for O'Conner until after the Roberts nomination was completed.
Then he waited a couple of weeks, and then nominated Miers.
That went for a while, then she withdrew in no small part because Specter/Leahy held a joint press conference where they essentially called her unqualified and sent her questionare back to her for a re-do, the first time they said that that had ever happened.
Then he nominated Alito, but he took some time for that as well.
Specter just complained that the committee didn't get to shoot down Miers (he didn't say it that way, he said she was taken out by talk shows, instead of by the committee).