I put he was okay, I always looked as Gary as a mentor in an odd way. Even though he was conceited and always one step ahead of Ash, he actually wanted Ash to succeed. Around Johto, he got a hell of a change, but at times I did miss him as annoying brat that always bothered Ash. But during the league, I saw how Gary and Ash in battle were really giving their all. Since in the past, they never really got much battling until pre-Johto when Gary's Eevee beat the living crap of Pikachu, the battle opened Ash's eyes, and as then they started to see each other once in a while, but more acting like friends then rivals.
Gary played a huge role in Ash's life, and after Ash beats him, its surprising how he decides to follow in his grandfather's footsteps. Okay I was bored, but eh, my little stupid rant.