Second edition of "Semantic Web for the Working Ontologist"
I have been extremely busy with work so I have only been able to spend about 90 minutes so-far with the second edition but I hope to give it a careful reading when I am on vacation in a few weeks.
This book is an excellent guide for anyone who wants to invest a fair amount of time to learn how to write semantic web enabled applications: a very comprehensive book.
I recently bought a eBook copy of Bob DuCharme's short book Learning SPARQL
Querying and Updating with SPARQL 1.1 that I would also like to recommend as a fairly easy introduction to using SPARQL repositories and generally using SPARQL in applications.
If two good new semantic web books were not enough, I have also had fun recently experimenting with Clark & Parsia's new Stardog RDF datastore that offers fast data loading, fast SPARQL queries, OWL 2 support, and built in search.