I work with several dozen AdWords accounts and at one point I remember seeing VERY DETAILED change history data, including bid changes, word changes, etc.
Due to client issues, sometimes when a project ends, I no longer have access to that account - so this may still apply to a very large account I was running for a while.
Lately, none of the accounts I am working with seem to show this level of detail. All it shows is budget updates, nothing to do with keywords or bid changes or anything other than budget.
I find this startling as I mostly stopped keeping detailed notes of changes as I assumed that change history would account for them. Fortunately this is mostly no big deal as my memory is pretty good and I keep a fairly decent history via client updates.
Do others find that View Change History in AdWords is different now on some accounts than others?