I read up on What's New in 10.2? However, I would like to get a link from you, where I can read up on 'The New Validation Rules introduced in 10.2'?
This will help us in making a decision to upgrade from AcrGIS and ArcFM 10.1 to 10.2'. Currently, we do not have much validation rules in 10.1 and we see that final posting is done where if we had more stringent validation rules, it should not have posted because some basic values in some of the attributes in the features were missing.
Thanks for the clarification. You can find the complete list of Validation Rules provided with ArcFM here: ArcFM Validation Rules
The only new rules are related to FM 2.0 and are listed in the link above and tagged with FM 2.0.
Its not very difficult to develop custom rules depending on the level of complexity required. Additionally you could elicit our services team to develop any rules you desire. I would suggest talking to your SAM regis dinkel if you are interested in the latter option.
Hopefully this helps.
Let me know if you have any further questions.