you have to understand that gaga's mainstream gays won't care about this "old man," and tony's fans probably don't think gaga is worthy of collaborating with him.
Duets II debuted with 180k, I would expect this to do about 120 with the same promo. Or much more if the promo is effective (advertising to houswives who feel cultured by listening to Jazz music).
I don't why everyone thinks this will be a huge seller/hit with the critics. Since WHEN has an album of jazz standards by King Of Schmaltz Tony Bennett been likely to be critically acclaimed? It sounds like something to soundtrack Starbucks and or Barnes & Noble. It's not going to be a...hit album.