The first Wicket in Action review is in. Geertjan Wielenga writes:
[I]f you're new to Wicket look no further. "Wicket in Action" provides everything you need. In particular for beginners, chapter  ("Building a cheesy Wicket application") is excellent: it shows you step by step how to create a pretty advanced Wicket application... and covers 30 pages. That's pretty impressive and it's a very thorough introduction to what Wicket offers you.
Thank you Geertjan for your kind words! They made my day!