Previous Times anniversary collections have (from memory) just had a puzzle for each year and a short introduction. This one is like the 80-year collection of Telegraph puzzles which appeared a few months before it - one puzzle per year plus some other information. This other stuff is more varied and entertaining than in the Telegraph book, partly because of the Times puzzle's reputation as the best and/or hardest daily cryptic crossword. We get Max Beerbohm's famous impossible puzzle, early correspondence about whether there should be a Times crossword, and some good poems and reminiscences including coverage of the annual Crossword Championship and plenty of interesting but less familiar stories. Oddly, the "Provost of Eton and egg-boiling" legend is not included.
Flaws: the considerable changes in the style of the puzzle itself are not explicitly described - you have to read between the lines a bit or tackle the puzzles themselves - some of the older ones are absolute beasts for solvers under 50 years of age. Hooking up puzzles to news stories ("6 May 1994 - Channel Tunnel Opens" and so on) implies (not necessrily accurately) that relatively little effort was made to choose representative or interesting puzzles.
Maybe next time - if an 80-year book comes out in 2010...