V9 change tracking recorded all the values of a column for the before snapshot, regardless of the filter in the query. V10 will only build the tracking with the results of the query, so not all records are tracked. If a client wants to know, for example, a person that changes their state to MA, the event will not trigger since the record is not in the change database until the record switches to MA in the database. You can use a "new record" query and trigger each time the query returns a record in MA but you do not have the ability to know what the previous value was for that record,.