Don't worry about Kobe leaving. He just said what he said to motivate Shaq to get to his MVP form, to convince Phil to coach a couple of more years, and to make the Lakers pick some players to stay competetive. Once all this happens, then Kobe will definitely sign with the Lakers.
He has too much to lose by leaving the Lakers.
The Lakers provides KObe with the second largest media market, the great history of the Lakers, and Los Angeles provides the best way of living in the country.
His family is comfortable in Los Angeles and his family is the most important thing in his life.