I cant find anything on what new features come out with SSAS 2017 for a multidimensional database. the only thing i can find is updates with the Tabular. any insight would be appreciated.
SSAS 2017 is primarily focused on new tabular features. There is a new compatibility level for tabular (1400) but no new compatibility level for multidimensional.
There are several discontinued and deprecated features, mainly for the multidimensional mode, and the default mode when installing is tabular now.