We’ve been hearing that some changes are afoot at Yahoo’s (NSDQ: YHOO) Santa Monica-based entertainment properties, and Yahoo Music might be the one most affected, and could include Yahoo TV as well. An announcement might come as soon as tomorrow. Some changes along those line are expected as new CEO Jerry Yang is in the midst of his 100-day review of the company. WSJ suggested earlier this month on Yahoo Music changes.

For Yahoo Music, it might mean the closure of its subscription music service, which has never really gained any traction against competition. The unit has about 250 to 300 staff, and it could involve some layoffs, though nothing major. Other property which has been on the rocks is Yahoo TV, which has struggled to maintain its identity in face of other entertainment blogs and destination sites. Yahoo PR didn’t respond until publish time.

Another trial balloon I will float right now: how long before Yahoo considers closing its Santa Monica offices, and move the properties back up North? No inside info on it, just my hunch on a long term change that might come.