I enjoyed the level of information in The Penguin History of the Second World War(previously published as Total War: The Causes and Courses of the Second World War by Peter Calvocoressi, Guy Wint, R. John Pritchard).
I looked at the reading suggestions in the booklist in the wiki, but I can't tell which of them, if any, have a similar level of depth.
Also, as a side note, has the book I referenced been discredited or anything? I don't read a ton of history and I really enjoyed it. I would hate to think it was wasted effort.
edit: spelling
I'd strongly recommend John Keegan's The First World War. Keegan's work often takes the form of an excellent synthesis of the available material conveyed through an effective and compelling narrative. His writing is both clear and understandable, pitched to an educated but non-specialist crowd. He is able to incorporate social history without losing the thread that most of us want in our military histories. I read this volume when it first came out, in 2000. I was on the job market, and it kept me calm while waiting for the cattle-call interviews in which the American Historical Association specializes. I recently reread it, 15 years later, and it's still very good.
Strachan and Howard's books in that list are a safe bet. I'd also recommend War of Attrition by William Phillpott and The Great War by Peter Hart.
Also consult /u/NMW's reading list: