Mark, this may not be the answer you are looking for, but are you sure you would like that property set to true by default? And if you do, would you like it to be checked by default only on new pages (as you create them), or should it be checked any time an editor edits a page? Also, should the editor be able to change the value - or do you simply want it to always be true, for some implementation reason? First of all, you should be aware that setting the Mark Page as Changed property to true when saving a page triggers some specific behaviour in EPiServer. For instance, if subscriptions are activated, the page would be included there as well as in lists of the most recently changed pages, and similar. That is part of the reason why there exists such a checkbox - so that editors can make minor modifications to a page without triggering these additional functions. If this is still something you would like to achieve, I guess one option would be to hook into one or more of the page-related events triggered by the DataFactory, and tweak the property value in that code. Depending on the answers to the questions posed above, you could decide the correct event to hook into - there are numerous events related to various page tasks, such as creating, deleting, saving or publishing pages. In the event handler for such events, you can access the PageData representation of the page to tweak property values.

Thanks Roger, that's pretty much what I expected - a client asked the question, but they're happy with the reason why there's no default for this.