Double money from £20k (if that's what he's on) to £40k. That will make him one of the top earners once Bent, Given, Dunne and Ireland are gone, so he couldn't complain there. Gabby might be on more but he's a senior player and our all time top Premier League goalscorer.
Then I'd expect him to go after next season, but at least the contract extension will allow us to command a huge fee.