World Coin Book Help

The Circulating Issues book is supposed to contain only the coins that have really circulated. So you will not find any of those shiny proof issues made for collectors. I never possessed it but was told that some commemorative issues that were also used for circulation could not be found in that book.
So it depends of which coins you have in your collection, to decide if you need the regular issue or not.

is there much of a difference in con value between 2005-2007 versions

It is always best to get the MOST informtion possible consistant with your collecting interests and your budget.

All catalogs have limits. The Krause "Standard" series are best for the average world collector, but there are numerous supplements once you start to focus. If you look at the US listings in Krause - they are OK but less complete than Red Book and far less complete than Breen's encyclopedia. The same goes for every other series of coins.

If you look in Krause for the Mexican Profile Eagle series of coins the entire entry covers less than 2 pages. But the same subject is treated at book length in Hubbard and O'Harrow's book "Hooknecks". You could not hope to collect Profile Eagle coins intelligently with only Krause.

I hope that is a clear expression of my thoughts.