Usually I blog about Business Intelligence, but BI is not the only field I work on. I born as developer and I recently co-authored a book about LINQ with Paolo: the title is Introducing Microsoft LINQ, we created a dedicated site where you can find blog, sample chapter, code and corrections (while a book is written during development before the beta, there is always some last minut change). It will be available on May 16, 2007 and it can already be ordered.
Even if LINQ is not directly related to BI, a possible LINQ to MDX implementation would be very interesting. Is there someone already working on it?