Here are the new fields for the event entity:

Basic ones:
name
comment
type
dates (like any other entity with those)
time (start time for the event)

Trickier ones that would be useful:
artist (look at artists linked to it)
location (look at areas or places linked to it)

Events also have aliases and annotations like other entities.

The mmd-schema PR is at https://bitbucket.org/metabrainz/mmd-schema/pull-request/19/mbs-6201-mmd-schema-for-events/diff