on 21 June 2009
This book broadly covers not only the data mining functionality in Analysis Services but also that in Excel 2007 (which you might not even learn about if you're focusing on Analysis Services only) and provides good, hands-on examples of everything. For my background (well acquainted with SQL Server but not with BI or Excel) it suited my needs perfectly.
This book is of intermediate level, being neither an exhaustive reference of everything (get something like "Analysis Services Unleashed" for that) nor a starter book for people who know nothing about database development. And while it does cover MDX and OLAP, the focus is primarily on DMX (for data mining) and you probably won't be able to learn MDX from it -- but that's OK, because you're going to want a separate book for that anyway if the Report Services designers and Excel pivot tables can't do it for you (try "SQL Server 2008 MDX Step-by-Step", I'm having good experiences with it).