Bought this before we travelled around the world for 4 months with our 4 and 2yr old - we went from the UK, USA, Oz, NZ to Malaysisa and Borneo
It really didn't give us anything new we hadn't gained from the general Lonely Planet books.
Of course you have to plan, of course you need to make certain some standard facilities are near by and of course you need to think about safety - but a standard trip to London would prepare you for that.
We found all the countries we visited geared up to travelling with kids, hotels/restaurants would go out of their way on portion size / healthy eating and most countries have officially sanctioned tourist offices - these were especially useful in NZ and Malaysia.
I would recommend this if you've never taken your kids on holiday or you suffer from nerves at the thought of getting on public transport with them. Also, it is another book to carry - and that weight needs to be signicantly valuable!