Thought i'd let you guys know of some books i have been reading that are pretty good, They are all from Manning which I am really starting to like that publisher more and more.
Art Of Unit Testing: Easily the best unit testing book I have read (and I have read a few). Great for newbies and those still getting to grips with how to test anything more than the most trivial of examples. It is the book i would recommend to people looking to learn to do TDD well. Note the examples are in C# but they really dont require indepth knowledge of .Net, in the same way all the other books are in java and I havent written a line of a coffee flavoured code in a decade. In saying that the tools are all .Net based but i am sure there are Python, Ruby and Java equivilents avaliable for most.
NHibernate in Action: Pretty much the same as the Hibernate book but shows all the .Net stuff you can do. its also a bit more up to date that the original Hibernate book (which has since had a second release). .Net devs nusing NH need* this book.
IronPython in Action: not a bad book... it does exactly what it intends, it teaches .Net devs about python on the CLR. The question is: Do you care? For me it was something of interest, i doubt I'll ever use it in production. As a side note for the .Net kids i think the path of C# => Boo => Python =>Ruby is the one to take for the typical C# developer**. It keeps the "barrier to entry" low for the next step so you are picking up one new thing at a time (ie new syntax, dynamic language contrainst, DSLs and other scripty weirdness) and by the end of the process you have 4 languages under your belt in about the same time it would take to do the C# => Ruby jump.
*OK no one needs anything, especially as the NH doc a pretty good, but you will be severely hindered without it.
** VB.Net devs; you know you will never learn another language, you have had years to do so!