This issue is surprisingly light on action but makes up for it by being one of the best world-building issues I've ever read. Joshua Williamson explores the nature of The Speed Force with surprising economy. He does a fair job of developing August as a character and gives Dr. Meena Dhawan a great introduction. Best of all, we get a nice scene between Barry and a teenage fangirl who is literally running out of control that showcases that Barry Allen's greatest power is his sense of compassion - not his speed.
The artwork matches the fast-paced story, stride for stride. There's a sense of motion to everything Carmine Di Giandomenico draws so even the static scenes of two people just standing there and talking have a certain sense of energy behind them. And the colors by Ivan Plascencia are perfectly eye-catching.