Tracking area management is done to maintain balance between paging signalling and TAU procedures. Tracking area management comes under the mobility management and controlled by MME. In network deployment and management, size of each tracking area is decided.
MBMS is a kind of service which is subscribed by UEs and MBMS content provider provides the service. It is more inclined towards the service rather than network management. It is network decision whether it want to deliver content by using the MBMS channel or dedicated bearer.
If network decides to deliver content using MBMS network nodes then first it defines MBMS Service Area (consists of cell(s)).
Now network should find out list of MBSFN Areas which cover the cells comes under the MBMS Service Area.
Now the selected MBSFN Areas come under the same tracking area or different tracking area, it does not matter to enable this service. If UE is in idle mode and re-selected another cell which is part of ongoing MBMS service then it will continue receiving the content. If tracking area of a newly re-selected cell does not match with the present list of TAI then UE triggers TAU procedure. I don't think any relationship between Tracking Area and MBSFN Area.