O'reilly is a class act and this little C#-5 intro/ref -->5 update is outstanding. The hot topic in C#-5 is Linq and databasing, and that just happens to be where this author shines. I was surprised that it covers a lot of procedures, tips and tricks in way more than just 5.0, but does hit the major highlights and differences from the 4.0 series. This is NOT a book for oop or C# beginners! I recommend Herb Schildt's 950 page opus on C# 4.0 The Complete Reference for beginners instead. Schildt assumes NO programming background (I mean no-- not even basic, cobol, fortran, pascal... let alone the C series), whereas this 5 update assumes you know both C# and oop. Insiders know that since C++ has the whole C library, old time programmers like me can "get away" with using C++ without a single non-structured, oop command. Not so with the 5 reference-- all the examples, tips and hints assume you've got a solid background in not just the C series, but oop techniques. In fact, I'd even go so far as to say that if you haven't done at least intermediate work with Linq and databasing, you might get a little lost, but with help from the web and or Safari (co owned by Oreilly) most any C# programmer will get a LOT out of this ref. (BTW 200 pages isn't exactly a "pocket" fit unless you don't want anything else in that pocket! The awesome index does make it an outstanding reference to keep right near your computer).
A caveat a lot of reviewers forget to add: this book, like most others, assumes your development work is in .NET and "traditional" business type applications of the framework, and NOT XNA/gaming. Since that's my field, I just want to let fellow game programmers know that this one is no different, however, the database and Linq info are equally helpful if you're programming agent/avatar functions in MMOGs using SQL or other dbms calls. Sooner or later, we all are going to have to get up to speed on these hot database topics in 5 as well as half dozen others, and this book is a great place to get both the 40,000 foot view and a lot of detail in one place. The fact that there are very few good, up to date 5 books out there cuts two ways-- there also hasn't been a lot of time to evalutate the code in this book. The few I've tried compile just fine, but I'm also leaning heavily on O'reillys reputation for scrubbing the heck out of their author's code with technical reviewers PLUS the fact that most of the examples used are very short. That said, I've NEVER found a book that doesn't have some coding errors, but that can be half the fun if you don't mind a little sleuthing and the errors aren't severe/logic level, but fairly simple syntax debugs. The one's I've tried from this book have zero "bottom debugger" warnings in Visual Studio, which you'd (at least) expect when buying a "finished" product!
A few cool tables, exhibits and highlights include: -- Full list of identifiers and keywords; -- Full list of operators in order of precedence; -- 6 kinds of constraints; -- Most commonly used exception types; -- Composing sequences diagram; -- Table of query operators; -- Complete list of preprocessor directives; and much more, including a GREAT index. There is NO BLOAT in this little book-- headings are immediately followed by glossary-like, practical applications, limits, and practical advice, then code examples and exceptions.
One warning: I ordered this with a couple other texts and it is so small that it came crushed to heck by the big boys it rode with. I had to sandwich it between two texts for two days to get the pages to straighten out. Advice-- order it alone due to it's small size, not with other bigger books!