Fastball Max velocity and average velocity
Ian Kennedy – 93.4 max, 90.66 ave.
Zach Kroenke — 93.1 max, 90.62 ave.
Mike Dunn — 96.6 max, 93.85 ave.
Grant Duff — 96.3 max, 93.39 ave.
Since there is so much hype behind him, I'll post Steven Strasburg's veleocity as well:
Steven Strasburg: 100.5 max, 96.78 ave.