The April release of Power BI Desktop enables end users to change visualization types on a deployed report in the server.
This an interesting feature that should turn some heads, but might cause confusion. The product and development teams thought ahead of course and makes it a Preview feature for now plus has to be activated on the report. This allows control on which reports it is used on as well as individual visualizations can have the featured turned on or off.
The feature will probably preview until some good feedback is received to improve this enhancement. It looks like the new feature will be well received and promoted. The changing of select measures as well as axis selections are available as well.