Wooz said:'A bit better' is a bit of an euphemism, in my opinion. The smallest IV NPC has more personality and credibility than anybody in say, F3.
We're not comparing it to F3.
Compared to GTA III, VC and SA, the span is a bit wider, especially because you chat with them more on those stupid-ass dates, but as I said, while the main character is infinitely better, the tradition of solid characterization has been there for some time.
In III...well ok Catalina and Maria are just annoying as fuck. Donald Love is good, tho'. Also, I do so like el Burro.
In VC, the game really thrives on archetypes. Ken Rosenberg is the ultimate archetype, and it works really well, and Lance Vance is a good plot staple as well. But Avery Carrington has some of the best writing of any GTA character. Also, Love Fist is hilarious.
In SA, Tenpenny was better than he had the right to be, but it was Torino that stole the show. Also, people easily miss how important a well setup annoying character that you can punish later (OG Loc) is. Also, Woozie, man, Woozie.