Leon of After Nature has posted on Dr. Neville, and shared with me an article on realism and universals in Peirce, Harsthorne, and Whitehead. I must admit, Neville's work is amazing! Like Leon, I have met him several times, e.g., at his talk on cosmic creativity at Southern Illinois University, and at the Society for the Advancement of American Philosophy. I can confirm that he's a nice guy, and since we're on the topic of leading thinkers who are nice guys, I will extend that to Joseph Margolis and Mitchel Aboulaffia, among others.
For a detailed discussion on the topic, see "Experience and Philosophy: A Review of Hartshorne's Creative Method and Philosophy." What is key in this is the difference between what is described as "Aristotelian" and "Platonic" notions of universals; e.g., whether universals are generated immanent within nature (Aristotle) or whether they are transcendent to natural existence (but not reality) (Plato). One thing that Neville discusses that is new to me, are the precise arguments for the temporality of the particular instantiation of a universal.