Well, the book isn't as technical as I would've liked, but I guess the author did kind of say that up front in the introduction to this book. It's not really a programmer's book for SharePoint. HOWEVER, having said that, if you've never done SharePoint development before (ever), then this would be a pretty good place to start. If you're an experienced developer with a background in ASP.Net and/or Silverlight, then you will be able to skip a good amount of stuff and just focus on what's different/new when developing in SharePoint.
Why 4 stars and not 5? Well, because sometimes the instructional exercises are not clear about when/where certain steps are to be performed. As a book geared towards those who have never done SharePoint development before, this is a big deal. In fact, some of the steps are just plain wrong (it looks like the author may have been using a Beta or Release Candidate version of SharePoint 2010--based on some of the screenshots that appear in the book--but even so, there is no errata at Wrox's site. And, I didn't post one because it was too much of a pain to do so). In particular, Chapter 4, pp. 155-156, steps 7-15 are not correct. In fact, in the later steps, looking at the Site Settings page in SharePoint, there is no Look and Feel section anymore (at least, not as a major category header) and I could not find where the author was talking about to apply a custom master page that was created in this exercise as the site's master page.
Other than that, though, the book is overall very good about explaining the high-level concepts pertinent to SharePoint 2010 development--and I do mean high-level; this book is really geared to brand new SharePoint developers with possibly little previous development experience.
