Finished the book yesterday, and wow... excellent book... Now if I only had time to re-read the full series...

Masa:
Voldemort had 6 horcruxes + himself = 7 Parts of his soul.
Diary, Locket, Cup, Diadem, Ring, Nagini and Himself.

Voldemort didn't know that his soul had ripped yet another part, creating an eight piece... thus there were 7 Horcruxes + Voldemort.

That is why when Neville destroyed Nagini, Voldemort was still alive...

Diary - Harry with Basilisk fang
Ring - Passed to Dumbledore's hand... destroyed by Snape's Killing Curse?
Locket - Slashed by Ron with Gryffindor's Sword
Cup - Basilisk fang by Hermione
Diadem - That wierd fire spell by Crabbe
Nagini - Slashed by Neville with Gryffindor's Sword
Harry's Horcrux - Killing Curse by Voldemort
Voldemort - Rebounded Killing Curse

Heck... Crabbe helped bring down Voldy...