One tragic element of the left in Britain, and I include myself in this (sometimes), is that they tend to take themselves far too seriously. So, the critics of Roberts' book can come across as bigoted and pompous. Let's get it straight - Churchill's History of the English Speaking Peoples is fairly right-wing, patriotic (not nationalistic), and has a tendency towards blood and guts history. What else would you expect from Churchill? All Roberts does is portray the 20th Century in the same vein - and let's face it - much of the 20th century was extremely bloody and the English Speaking Peoples can be justifiably proud of much of their role in mitigating this. No book summarising this period could possibly be completely objective (can any book worth reading?), but, in my view, Roberts does a pretty good job - given the role of the book. Like Churchill's original manuscript, Roberts' update is extremely well-written, has fantastic pace, is generally well-researched with copious references, and reads well. Covering probably the most interesting century in the history of mankind, not to mention the best-documented, in a single volume is not going to please everyone - take it as a good place to start a more detailed study.
Personally, I found much of Roberts detail extremely interesting, and particularly liked his thorough examination of the rise of the USA - warts and all. These days it is fashionable in some quarters to ignore the huge amount the USA has done to try to make the world a better place, and concentrate on their mistakes and the many imaginary hidden agendas that country is claimed to have. There is absolutely no doubt that without the intervention of the USA, Hitler would have smashed the UK and the USSR. A strictly neutral USA would not have been attacked by Japan, and China, India, and SE Asia would have fallen under Japanese rule. It is also possible that a neutral USA would not have been moved to prevent Japan taking Australia and New Zealand as well. Hands up anyone who thinks all that would have led to a better world!
There are mistakes in this book, kindly pointed out by the always perfect Economist. I've never read a history yet that didn't have errors, any worth their salt remedy things in subsequent editions. I have no doubt that there will be other editions of Roberts' work, but why wait for them when you can enjoy the current version?