When existing CRM Online organisations were updated with the latest Service Release (December 2012 Service Release at the time of writing) the majority of the new features were not activated by default. I reckon most administrators will not have enabled the new features (wisely in my view given the problems they introduce and the inability to de-activate them). However, when new organisations are now provisioned the new features in the December 2012 Service Release are automatically pre-activated.
This presents a problem because unless you were fortunate enough to have provisioned all the Dev/Test organisations you required **before** the service update was applied, (and not "accidentally" enabled the new features in any of them) you are now unable to spin up any new organisations (e.g. for Dev/Test purposes) that mirror your pre-existing production environment.
One should note here that simply "disabling" the new FlowUI forms in new organisations is NOT sufficient. Even the Classic forms are rendered differently once the new forms are activated and the new FlowUI forms get included in solutions (because you modified them to disable them...) Most importantly however the Lead qualification dialog no longer appears, account, contact and opportunities are always created and duplicate detection rules ingnored in the process. There are most probably other issues that have not yet come to light.
At the moment I think (but have not yet validated) that Dev/Test could continue in On-Premise deployments. Not a very palitable situation for a smaller client but at least there might be a way out right now? In the future however I can't see this working anymore as the version/feature gap between CRM Online and CRM On-Premise widens.
I understand why Microsoft wants to have the very latest features in new trials but if proper development and testing is to be supported there must be a way to provide CRM Online organisations that match existing environments. At the moment this is not possible and further more I've been told in a support case that this is "By Design". This MUST be changed.
##Suggestion## A work around might be for any **additional** CRM Organisations made in an Office 365 account to be provisioned **without** new features activated? In other words exactly as if they had been a pre-exisiting organisation that was later upgraded to whatever the latest service release is at the time? Administrators could then choose to activate new features (e.g. to test them out) or refrain from doing so (e.g. to mirror their existing production environment for Dev/Test)