Joe Castiglione mentioned on Sunday's radio broadcast that he will be taking some time off after the All-Star break, and that Glenn Geffner and David O'Brien will be calling the Toronto series.
[update] I agree with the notion that this is a dry-run for Your 2008 Red Sox Broadcasting Team. Joe made a point of sort of announcing that he would be away, mentioning O'Brien and Geffner by name. Consistent with the "Out Of Sight, Out Of Mind" approach in the booth, it is unusual for either announcer to mention O'Brien when he is not there, or to mention Geffner [actually, who would mention Geffner?]. O'Brien doesn't talk about games he did for ESPN much, and of course, Jerry Trupiano's name, voice and existence are verboten. Poor old dead Ken Coleman gets more run than Trup.
Your MLB Announcing Schedule for 9/1 – 9/7
12 hours ago