I have it on pretty good authority that Fenway is thinning its beer selections this season. Not sure it's entirely because of this deal (maybe some skus just didn't sell enough), but from what I was told it is pretty significant.
From what I recall, the following won't be in Fenway anymore (and this is from memory as I wasn't going to ask him to forward me the email he was reading from): Jack's Abby, Smuttynose, Narragansett, Goose Island, Blue Moon, Blue Point, Leinenkugel... probably a few I'm forgetting as well. I think he said they would only be carrying 18 beers total between bottle and draft.
It's also worth noting that Sam Adams makes Angry Orchard, Twisted Tea, and Truly hard seltzer. This deal included all of those as well and they should all be part of the Fenway assortment.