How does Ponyboy's opinion of the Socs at the end of Hinton's The Outsiders differ from his opinion at the beginning?

At the beginning of the book, Pony assumes the Socs are all enemies. By the end, he realizes they are just people with problems like everyone else.

As the book opens, Pony is afraid of the Socs, the greasers' rival gang. He thinks they unfairly target greasers. The Socs are the rich kids, and they have all the breaks.

Greasers can't walk alone too much or they'll get jumped, or someone will come by and scream "Greaser!" at them, which doesn't make you feel too hot, if you know what I mean. We get jumped by the Socs. . . the jet set, the West-side rich kids (Chapter 1). 

When Pony meets Cherry, he changes his mind about the Socs, at least to some degree. Cherry tells him everyone has problems, regardless of whether they have money. Social class is not everything. She makes Pony stop and think about the Socs as people, and not just the enemy, when she tells him things are “rough all over.” 

I shook my head. It seemed funny to me that the sunset she saw from her patio and the one I saw from the back steps was the same one. Maybe the two different worlds we lived in weren't so different. We saw the same sunset (Chapter 3). 

This new understanding is somewhat enhanced by the aftermath of the fight in the park when Johnny kills Bob. Johnny and Pony are forced to go on the run. When they return, Pony finds some of the Socs are reacting strongly to the incident. Cherry turns “spy” and tells the judge Bob was drinking and it wasn’t Johnny’s fault. Randy tells Pony he doesn’t want to fight anymore and won't participate in the upcoming rumble, saying,

I'm sick of all this. Sick and tired. Bob was a good guy. He was the best buddy a guy ever had. I mean, he was a good fighter and tuff and everything, but he was a real person too. You dig? (Chapter 7) 

Cherry and Randy both make Pony look at Socs differently, but not in the same way. Cherry makes him realize not all Socs are out to get greasers. Randy makes him realize it is possible for Socs to change. Pony emerges from the experience changed and with a different perspective on the Soc-greaser conflict and the Socs themselves.