Does an HSRP VIP factor into the PIM designated router and IGMP querier election on a segment? Should they be located on the same interface or device? What would be the effects of having them separate?
They really have nothing to do with each other. The client workstation will send unicast data to the VIP, but multicast will be sent to the group address. The DR will then forward the data up the tree. By default, if there are two multicast routers on a segment, one will be the DR and the other will be the IGMP querier. IGMP joins and membership query/reports are all multicast.